Probe apparatus', systems and methods for use in non-destructive evaluation

Abstract

A probe apparatus for use in the non-destructive evaluation of an object under test comprises a transducer arrangement configured and / or operable to direct an ultrasonic beam towards the object under test, a compliant element configured to engage the object under test, and an intermediate member interposed between the transducer arrangement and the compliant element. The intermediate member and the compliant element are arranged so as to define an interface therebetween. In some aspects, the intermediate member and the compliant element are configured and / or operable to retain a fluid disposed at the interface between the intermediate member and the compliant element. In other aspects, the probe apparatus are configured and / or operable to control an angle of inclination of the compliant element so as to reduce a deviation in the ultrasonic beam propagating in the object under test.

Description

[0001] PROBE APPARATUS’, SYSTEMS AND METHODS FOR USE IN NONDESTRUCTIVE EVALUATION

[0002] FIELD

[0003] This relates to probe apparatus’, systems and methods for and for use in nondestructive evaluation of an object under test.

[0004] BACKGROUND

[0005] Non-destructive evaluation (NDE) techniques are used extensively across a wide range of industries in order to determine the properties, condition, integrity and / or behaviour of objects, such as machines, components or materials.

[0006] As the name indicates, unlike traditional testing techniques, with NDE techniques the object under test is not significantly damaged or changed by the evaluation and so the evaluation can be carried out on objects which can then be used in service. Indeed, in some instances NDE techniques can be used to determine the properties, condition, integrity and / or behaviour of objects while in service.

[0007] One particular application for NDE is in the area of weld testing, the nondestructive nature of NDE equipment and techniques permitting the quality of welds to be evaluated before entering and / or during service. While NDE techniques provide significant advantages over traditional testing techniques, conventional NDE techniques require waiting for all layers of the weld to have been deposited and for the weld to cool to ambient temperature, leading to requirements for reworking and / or reduced throughput.

[0008] More recently, NDE equipment and techniques have been developed which aim to evaluate welds during and / or immediately after the welding process itself, rather than having to wait for all layers of the weld to have been deposited and for the weld to cool to ambient temperature. For example, conventional NDE techniques require waiting for an individual weld pass or layer to have been completed and for the weld pass or layer to cool to ambient temperature, leading to an increase in the time required to complete the overall weld, as well as an increase in the energy costs associated with repeated cycles of heating and cooling. It is well understood that the quality of a given weld is dependent on a number of variables present during and / or immediately after the welding process, with deviations in one or more of the variables beyond set limits often resulting in reduced weld quality and in extreme cases welded objects which are unfit for purpose. While automation has allowed a greater degree of control over the variables effecting the welding process, in-process NDE offers the possibility for the quality of welds to be evaluated during and / or immediately after the welding process and / or the welding process to be better controlled to ensure weld quality.

[0009] While NDE techniques provide significant advantages over traditional testing techniques, conventional NDE techniques when working with objects at above ambient temperatures and limitations in terms throughput.

[0010] There remains significant technical challenges in the use of NDE equipment and / or techniques for in-process weld testing.

[0011] Another application for NDE is in the area of composite testing, the nondestructive nature of NDE equipment and techniques permitting the quality of composites and composite components to be evaluated before entering and / or during service.

[0012] The use of NDE equipment and / or techniques for composite testing during the manufacturing process presents similar technical challenges to those discussed in relation to in-process weld testing above.

[0013] SUMMARY

[0014] Aspects of the present disclosure relate to probe apparatus’ for use in nondestructive evaluation of an object under test, and to method for non-destructive evaluation of an object or objects under test.

[0015] According to a first aspect, there is provided a probe apparatus for use in the non-destructive evaluation of an object under test, comprising: a transducer arrangement configured and / or operable to direct an ultrasonic beam towards the object under test; a compliant element configured to engage the object under test; and an intermediate member interposed between the transducer arrangement and the compliant element, wherein the intermediate member and the compliant element are arranged so as to define an interface therebetween, and wherein at least one of the intermediate member and the compliant element are configured and / or operable to retain a fluid disposed at the interface between the intermediate member and the compliant element.

[0016] In use, the probe apparatus may be located on an object under test, with the compliant element subjected to a force urging the compliant element into engagement or enhanced engagement with the object under test. The transducer arrangement is configured and / or operable to direct an ultrasonic beam towards the object, with one or more properties of a reflected beam being detected by the transducer arrangement and / or another detection arrangement to determine the properties, condition, integrity and / or behaviour of the object under test. As will be described further below, a fluid is disposed within the probe apparatus, including at the interface between the intermediate member and the compliant element, the fluid acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element and onwards into the object under test. In the present probe apparatus, one or both of the intermediate member and the compliant element are configured and / or operable to retain the fluid disposed at the interface between the intermediate member and the compliant element.

[0017] The probe apparatus provides a number of benefits over conventional equipment. For example, the probe apparatus may obviate or at least mitigate the likelihood that the fluid will be evacuated from the interface between the intermediate member and the compliant element when the probe apparatus is in use, in particular but not exclusively due to the load force urging the intermediate member into engagement with the compliant element forcing the fluid from the interface. This has the benefit of maintaining the cooling effect at the interface, which may in turn facilitate use of the probe apparatus at higher temperatures and / or prolonged effective use of the probe apparatus at a given temperature.

[0018] Moreover, by obviating or at least mitigating the likelihood that the fluid will be evacuated from the interface between the intermediate member and the compliant element, the effective transmission of the ultrasound beam from the transducer arrangement into the compliant element and onwards into the object under test is maintained. This in turn may permit the apparatus to be subjected to a greater range and / or variation in load force. For example, the apparatus may be subjected to a greater load force so as to better conform with the object under test, without detrimentally affecting the ability to communicate the ultrasonic beam between the intermediate member and the compliant element and onwards into the object. Alternatively, the apparatus may be subjected to a reduced load force having obviated or at least mitigated the likelihood that the fluid will be evacuated from the interface, the retention of the fluid within the interface ensuring the effective transmission of the ultrasound beam when compared with conventional apparatuses without the reliance of said conventional apparatuses on the exertion of high load forces on the apparatus.

[0019] The probe apparatus may be configured and / or operable to facilitate dry-coupled inspection of the object under test, i.e. without a liquid couplant between the probe apparatus and the object under test.

[0020] Beneficially, dry-coupled inspection may facilitate faster evaluation of the object under test and / or obviate the risk that the liquid couplant might contaminate the object under test and / or the environment. However, it will be understood that in some embodiments the probe apparatus may employ a liquid couplant, e.g. a gel. The probe apparatus may find particular application in the areas of weld inspection, for example but not exclusively facilitating high temperature compliant weld inspection to be carried out - both after the welding process and / or on in-service welds but also during and / or immediately after the welding process and so may permit the welding process to be better controlled to ensure weld quality. This in turn may beneficially obviate or at least mitigate the need for re-working and consequential benefits in terms of greater certainty of schedule and / or reduced manufacturing lead times.

[0021] For example, the probe apparatus may permit high temperature, e.g. up to 350 degrees C, non-destructive evaluations to be carried out during the welding process. More particularly, but not exclusively, this may facilitate evaluation to be carried out between passes in a multi-pass weld, thereby obviating or at least mitigating the risk that defects present in early passes go un-detected until all layers of the weld have been deposited and which would otherwise require significant reworking or scrapping of the component and / or avoiding repeatedly heating and cooling the component which may negatively affect the quality of the weld. Thus, the probe apparatus may also reduce the energy costs associated with said repeated cycles of heating and cooling.

[0022] Alternatively, the probe apparatus may find particular application in the inspection of objects constructed using additive manufacturing techniques. In particular, the probe apparatus is considered to provide beneficial effects regarding the inspection of objects constructed using metal additive manufacturing, such as wire arc additive manufacturing (WAAM).

[0023] Metal additive manufacturing is a method of metal production which involves the addition of numerous layers in succession in order to produce a metal object. Metal additive manufacturing is a method unlike its subtractive counterparts, which form metal parts via the removal of material, or the shaping of material via machining, milling or forming, for example.

[0024] As discussed above, the ability of the probe apparatus to be configured and / or operable to facilitate dry-coupled inspection of the object under test ensures that the evaluation of any metal object produced via metal additive manufacturing may be completed faster, and / or may obviate the risk that the liquid couplant might contaminate the metal object under test. Furthermore, the ability of the apparatus to facilitate high temperature metal object inspection - both after the metal additive manufacturing process and / or on in-service metal objects but also during and / or immediately after the metal additive manufacturing process permits the metal additive manufacturing process to be better controlled and the assurance of metal object quality. This in turn may beneficially obviate or at least mitigate the need for re-working and consequential benefits in terms of greater certainty of schedule and / or reduced manufacturing lead times.

[0025] Alternatively, the probe apparatus may find particular application in the inspection of composite materials.

[0026] Beneficially, the probe apparatus may facilitate the inspection of components comprising composite materials while obviating or at least mitigating the likelihood of liquids contaminating the composite component, as may be the case in some conventional techniques.

[0027] As described above, the probe apparatus comprises a transducer arrangement configured and / or operable to direct an ultrasonic beam towards the object under test.

[0028] The transducer arrangement may comprise one or a plurality of transducers. One or more of the transducers may comprise or take the form of a piezoelectric transducer. Alternatively or additionally, one or more of the transducers may comprise or take the form of an eddy current transducer. Alternatively or additionally, one or more of the transducers may comprise or take the form of a capacitive transducer, e.g. a capacitive micro-machined ultrasonic transducer (CMLIT). Alternatively or additionally, one or more of the transducers may comprise or take the form of a dry-coupled ultrasonic test (DCLIT) transducer. Alternatively or additionally, one or more of the transducers may comprise or take the form of an electromagnetic acoustic transducer (EMAT).

[0029] The transducer arrangement may comprise or take the form of a transducer array. The transducer arrangement may comprise one or a plurality of arrays of transducers. In particular, the transducer arrangement may comprise or take the form of a phased array ultrasonic transducer (PALIT) arrangement. The transducer arrangement may be configured and / or operable to transmit and / or receive the ultrasonic beam. One or more of the transducers of the transducer arrangement may comprise or take the form of: a transmitter or emitter; a receiver; a transceiver.

[0030] The probe apparatus may comprise, may be coupled to or operatively associated with a driver device. The transducer arrangement may be coupled to and / or operatively associated with the driver device, for example an ultrasonic driver device. The driver device, for example the ultrasonic driver device, may be configured and / or operable to transmit a pulse. The ultrasonic driver device may be configured and / or operable to transmit an electric pulse. The ultrasonic driver device may be configured and / or operable to transmit a high voltage pulse. The ultrasonic driver may be configured and / or operable to transmit a high voltage electric pulse. The ultrasonic driver may be configured and / or operable to record a signal which corresponds to the ultrasonic beam received by the one or more receivers.

[0031] In use, the ultrasonic driver device transmits the high voltage electric pulse, causing the one or more transmitters to transmit an ultrasonic beam. The one or more receivers having received the reflected ultrasonic beam, the ultrasonic driver device shall receive a corresponding signal. The ultrasonic driver device shall then record the signal received.

[0032] Alternatively or additionally, the ultrasonic driver device transmits the high voltage electric pulse, causing each of the one or more transmitters to transmit an ultrasonic beam at an interval separate from each of the other transmitters, with the reflections from each of the ultrasonic beams transmitted being received by the one or more receivers. The plurality of receivers having received the reflected ultrasonic beams, the ultrasonic driver device shall receive corresponding signals, which the ultrasonic driver device shall record. Said recorded data may then be utilised in order to conduct advanced reconstruction in order to create a constructive interference in the wavefronts in question.

[0033] The ultrasonic driver device may comprise, may be coupled to and / or operatively associated with a processing system configured to interpret the electronic signal recorded by the ultrasonic driver device following the receipt of the reflected ultrasonic beam by the one or more receivers. The processing system, or at least part of the processing system may form part of the ultrasonic driver device.

[0034] The processing system, or part of the processing system, may be coupled to or operatively associated with the ultrasonic driver device. For example, the processing system may be located at one or more remote location. The remote location may comprise or take the form of a mobile device such as tablet, mobile phone or the like. Alternatively or additionally, the remote location may comprise or take the form of a control room. Alternatively or additionally, the remote location may comprise or take the form of a data store, such as an online data store.

[0035] The ultrasonic driver device may be configured to transmit information to the processing system. The ultrasonic driver device may comprise a communication arrangement configured to communicate the electronic signal corresponding to the ultrasonic beam received by the one or more receivers to one or more remote location. The communication arrangement may comprise or take the form of a two-way communication arrangement.

[0036] As described above, the probe apparatus comprises an intermediate member interposed between the transducer arrangement and the compliant element.

[0037] The intermediate member may comprise or take the form of a solid core.

[0038] The intermediate member may comprise or take the form of a wedge.

[0039] Alternatively, the intermediate member may comprise or take the form of a planar or substantially planar member or may have other shapes.

[0040] The intermediate member may be partially or wholly constructed from a plastic material. The plastic material may comprise or take the form of a thermoplastic material. In particular embodiments, the plastic material may comprise or take the form of polyetherimide, e.g. Ultern®. Alternatively or additionally, the plastic material may comprise or take the form of polyimide, e.g. Vespel®. The plastic material may comprise or take the form of a polyamide-imide, e.g. Duratron®. Beneficially, the intermediate member provides high strength and high temperature capabilities, facilitating use in high temperature in-process non-destructive evaluation of objects, such as welds during and / or immediately after the welding process, metal objects during and / or immediately after the metal additive manufacturing process or composite components during and / or immediately after the manufacturing process.

[0041] The transducer arrangement and the intermediate member may together form a transducer assembly of the probe apparatus.

[0042] At least one of the transducer assembly and the compliant element are configured and / or operable to retain a fluid disposed at the interface between the intermediate member and the compliant element.

[0043] As described above, the probe apparatus comprises a compliant element configured for location between the intermediate member and the object under test.

[0044] The compliant element may be partially or wholly constructed from elastomeric material. The elastomeric material may comprise or take the form of a silicone rubber material. In particular embodiments, the compliant element may be partially or wholly constructed from high temperature silicone rubber. Alternatively or additionally, the compliant element may comprise a hydrogenated nitrile butadiene rubber (HNBR) material. The compliant element may comprise an ethylene propylene diene monomer (EPDM) material.

[0045] Beneficially, the compliant element is capable of conforming to the geometry of the object under test and provides high strength and high temperature capabilities, facilitating use in high temperature in-process non-destructive evaluation of objects, such as welds during and / or immediately after the welding process, metal objects during and / or immediately after the metal additive manufacturing process or composite components during and / or immediately after the manufacturing process.

[0046] The compliant element may comprise or take the form of a cylindrical or substantially cylindrical element. The probe apparatus may be configured so that the compliant element moves relative to the intermediate member. For example, the probe apparatus may be configured so that the compliant element rotates around the intermediate member and / or the transducer arrangement. In particular embodiments, the compliant element may comprise or take the form of a rolling element. The compliant element may comprise or take the form of a tyre, wheel or the like.

[0047] The compliant element may at least partially define an internal volume. The internal volume may comprise or take the form of a chamber. The transducer arrangement and / or the intermediate member (e.g. the transducer assembly) may be disposed within the internal volume.

[0048] Alternatively, the probe apparatus may be configured so that the compliant element moves axially relative to the intermediate member.

[0049] The compliant element may comprise or take the form of a planar or substantially planar element. For example, the compliant element may comprise or take the form of a membrane.

[0050] The probe apparatus may comprise a support arrangement. The support arrangement may comprise or take the form of a mandrel. In use, the mandrel may form an axle of the probe apparatus.

[0051] The transducer arrangement and / or the intermediate member (e.g. the transducer assembly) may be supported, e.g. mounted, on the mandrel. The transducer arrangement and / or the intermediate member (e.g. the transducer assembly) may be fixedly coupled to, e.g. fixedly mounted on, the mandrel.

[0052] The compliant element may be movably supported, e.g. mounted on or coupled to, the mandrel. In particular embodiments, the compliant element may be rotatably supported, e.g. rotatably mounted on or coupled to, the mandrel. The probe apparatus may comprise a bearing arrangement for rotatably supporting the compliant element.

[0053] As described above, the intermediate member and the compliant element are arranged so as to define an interface therebetween, and at least one of the intermediate member and the compliant element are configured and / or operable to retain the fluid disposed at the interface between the intermediate member and the compliant element.

[0054] The configuration of the intermediate member and / or the compliant element so as to retain the fluid disposed at the interface may take a number of different forms.

[0055] For example, the configuration of the intermediate member and / or the compliant element so as to retain the fluid disposed at the interface may comprise or take the form of a surface treatment.

[0056] The surface treatment may be formed or otherwise provided on a distal surface of the intermediate member, i.e. the surface of the intermediate member which in use faces the compliant element.

[0057] The surface treatment may comprise or take the form of: one or more protrusions formed or otherwise provided on the intermediate member; one or more ridges formed or otherwise provided on the intermediate member; one or more grooves formed or otherwise provided on the intermediate member; one or more channels formed or otherwise provided on the intermediate member; and / or one or more bores formed or otherwise provided on the intermediate member.

[0058] The surface treatment may be formed by one or more of processes such as: milling, e.g. CNC milling; machining, e.g. laser machining; engraving; etching, e.g. acid etching; and / or sandblasting.

[0059] The one or more of processes may be applied to the intermediate member.

[0060] The surface roughness of the intermediate member may be selected based on the frequency and / or wavelength of the ultrasonic beam.

[0061] For example, the surface roughness may be selected to be: Ra < A / 10,

[0062] Where Ra is surface roughness

[0063] Where A is wavelength.

[0064] Beneficially, this may minimise or at least reduce wavefront aberration.

[0065] Alternatively or additionally, the surface treatment may be formed or otherwise provided on a surface of the compliant element which faces the intermediate member, which in use may be an upper surface or internal surface of the compliant element.

[0066] The surface treatment may comprise or take the form of: one or more protrusions formed or otherwise provided on the compliant element; one or more ridges formed or otherwise provided on the compliant element; one or more grooves formed or otherwise provided on the compliant element; one or more channels formed or otherwise provided on the compliant element; and / or one or more bores formed or otherwise provided on the compliant element.

[0067] The surface treatment may be formed by one or more of processes such as: milling, e.g. CNC milling; machining, e.g. laser machining; engraving; etching, e.g. acid etching; and / or sandblasting.

[0068] The one or more of processes may be applied to the compliant element and / or to the mould used to form the compliant element.

[0069] The surface roughness of the compliant element may be selected based on the frequency and / or wavelength of the ultrasonic beam.

[0070] For example, the surface roughness may be selected to be: Ra < A / 10,

[0071] Where Ra is surface roughness

[0072] Where A is wavelength.

[0073] Beneficially, this may minimise or at least reduce wavefront aberration.

[0074] As described above, in use, the probe apparatus may be located on an object under test, with the compliant element subjected to a force urging the compliant element into engagement or enhanced engagement with the object under test. The transducer arrangement is configured and / or operable to direct an ultrasonic beam towards the object, with one or more properties of a reflected beam being detected by the transducer arrangement and / or another detection arrangement to determine the properties, condition, integrity and / or behaviour of the object under test. As will be described further below, a fluid is disposed within the probe apparatus, including at the interface between the intermediate member and the compliant element, the fluid acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element and onwards into the object under test. In the present probe apparatus, one or both of the intermediate member and the compliant element are configured and / or operable to retain the fluid disposed at the interface between the intermediate member and the compliant element.

[0075] In some embodiments, the intermediate member and the compliant element may be reconfigurable from a first configuration in which the intermediate member and the compliant element are spaced from each other to a second configuration, e.g. in response to the applied load, in which the intermediate member engages the compliant element and which prevents the fluid in the interface from escaping.

[0076] Alternatively, the intermediate member and the compliant element may be arranged so as to always be engaged, the intermediate member and the compliant element being reconfigurable from a first configuration in which the intermediate member and the compliant element are engaged but which permit fluid in the interface to escape and a second configuration, e.g. in response to the applied load, in which the intermediate member engages the compliant element and which prevents the fluid in the interface from escaping. The probe apparatus may be reconfigurable from a first configuration, in which the distal surface and the internal surface are separate, to a second configuration, in which the distal surface engages the internal surface, the one or more protrusions of the distal surface and / or the internal surface respectively retaining a fluid in position at an interface formed by the engagement of the distal surface and the internal surface.

[0077] The probe apparatus may comprise an absorber.

[0078] The absorber may be coupled to and / or operatively associated with the intermediate member. The absorber may be coupled to and / or operatively associated with an external wall of the intermediate member, i.e. the surface of the intermediate member which, in use, is positioned vertically or substantially vertically.

[0079] The absorber is configured and / or operable to absorb ultrasonic waves.

[0080] Beneficially, the absorber may prevent undesired reflected waves / signals affecting the evaluation.

[0081] As described above, a fluid is disposed within the probe apparatus, including at the interface between the intermediate member and the compliant element, the fluid acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element and onwards into the object under test. In the present probe apparatus, one or both of the intermediate member and the compliant element are configured and / or operable to retain the fluid disposed at the interface between the intermediate member and the compliant element.

[0082] The probe apparatus may comprise an inlet arrangement. The inlet arrangement may comprise one or more inlets.

[0083] The probe apparatus may comprise an outlet arrangement. The outlet arrangement may comprise one or more outlets.

[0084] The inlet arrangement may be coupled to and / or operatively associated with a fluid arrangement. The fluid arrangement may be configured and / or operable to supply the fluid for disposal at the interface between the intermediate member and the compliant element. The fluid arrangement may be configured and / or operable to supply the fluid for disposal at the interface via the inlet arrangement.

[0085] The outlet arrangement may be coupled to and / or operatively associated with the fluid arrangement. The fluid arrangement may be configured and / or operable to remove the fluid from the interface. The fluid arrangement may be configured and / or operable to remove the fluid from the interface via the outlet arrangement.

[0086] The fluid arrangement may be configured and / or operable to supply the fluid for disposal at the interface via the outlet arrangement.

[0087] The fluid arrangement may be configured and / or operable to remove the fluid from the interface via the inlet arrangement.

[0088] The fluid arrangement may be configured and / or operable to simultaneously supply and remove the fluid.

[0089] The fluid arrangement may be configured and / or operable to sequentially supply and remove the fluid.

[0090] The inlet arrangement and the outlet arrangement may comprise or take the form of separate arrangements.

[0091] Alternatively, e.g. where the fluid arrangement is configured and / or operable to supply and then remove the fluid sequentially, the inlet arrangement and the outlet arrangement may comprise the same arrangement.

[0092] The apparatus may comprise a valve arrangement. The valve arrangement may be configured and / or operable to control ingress and / or egress of the fluid.

[0093] The fluid arrangement may comprise, be coupled to and / or operatively associated with a cooling arrangement. The cooling arrangement may be configured and / or operable to cool the fluid for disposal at the interface. In use, the cooling arrangement cools the fluid for disposal at the interface between the intermediate member and the compliant element. The fluid source subsequently supplies the fluid to the internal volume of the compliant element via the inlet arrangement, at which point the fluid becomes disposed at the interface. The fluid, having undergone an increase in temperature through use of the probe apparatus, is then removed by the fluid arrangement from the internal volume of the compliant element via the outlet arrangement. Whilst removing the high temperature fluid from the internal volume, the fluid arrangement may simultaneously supply fluid which has been cooled via the cooling arrangement to the internal volume, in order to replace the high temperature fluid removed. The cooling arrangement then cools the high temperature fluid removed, which may then be resupplied to the internal volume of the compliant element via the inlet arrangement.

[0094] The fluid may be configured and / or operable to act as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element and onwards into the object under test.

[0095] The fluid may comprise or take the form of a liquid.

[0096] The fluid may comprise or take the form of a coolant.

[0097] The fluid may comprise or take the form of a couplant.

[0098] The probe apparatus may be configured and / or operable to control an angle of inclination of the compliant element so as to reduce a deviation in the ultrasonic beam propagating in the object under test.

[0099] In use, the probe apparatus may be located on an object under test, with the compliant element subjected to a force urging the compliant element into engagement or enhanced engagement with the object under test. The transducer arrangement is configured and / or operable to direct an ultrasonic beam towards the object, with one or more properties of a reflected beam being detected by the transducer arrangement and / or another detection arrangement to determine the properties, condition, integrity and / or behaviour of the object under test. As will be described further below, a fluid is disposed within the probe apparatus, including at the interface between the intermediate member and the compliant element, the fluid acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element and onwards into the object under test. In the present probe apparatus, the probe apparatus is configured and / or operable to control an angle of inclination of the compliant element so as to reduce a deviation in the ultrasonic beam propagating in the object under test.

[0100] It has been found that a 1 degree difference in inclination of the inner and outer surfaces of the compliant element results in a much larger deviation in the ultrasonic beam path inside the object under test. For example, the compliant element often comprises a material through which sound travels at a reduced speed when compared to those materials which the intermediate member and the object under test respectively comprise. Thus, as an ultrasonic beam travels from the intermediate member to the compliant element, the beam is refracted, resulting in a significant change in the angle of the ultrasonic beam. A similar process of refraction occurs as the beam travels from the compliant element to the object under test. Where the inner and outer surfaces of the compliant element are maintained parallel relative to one another, the angle of the ultrasonic beam path inside the object under test remains unaffected.

[0101] Beneficially, the probe apparatus compensates for a deviation in the ultrasonic beam propagating in the object under test resulting from the ultrasonic beam propagating through a compliant element having inner and outer surfaces which are non-parallel.

[0102] The probe apparatus may be configured and / or operable and / or operatively associated with an arrangement to control an angle of inclination of the compliant element so as to reduce a deviation in the ultrasonic beam propagating in the object under test.

[0103] The probe apparatus may comprise a passive arrangement for controlling the inclination of the compliant element.

[0104] The probe apparatus may comprise a guide arrangement.

[0105] The guide arrangement may be configured and / or operable as a movement limiter. The guide arrangement may comprise or take the form of a mechanical fixture, frame or the like.

[0106] The passive arrangement may comprise one or more wheels. The one or more wheels may be configured and / or operable to control the alignment of the compliant element.

[0107] The probe apparatus may be coupled to and / or operatively associated with an active arrangement for controlling the inclination of the compliant element.

[0108] The active arrangement may comprise or take the form of an actuator arrangement.

[0109] The actuator arrangement may comprise one or more actuator.

[0110] One or more actuators of the actuator arrangement may comprise or take the form of a mechanical actuator.

[0111] Alternatively or additionally, one or more actuators of the actuator arrangement may comprise or take the form of a fluid-powered actuator.

[0112] Alternatively or additionally, one or more actuators of the actuator arrangement may comprise or take the form of a robotic actuator, e.g. a robotic arm.

[0113] Alternatively or additionally, one or more actuators of the actuator arrangement may comprise or take the form of a pneumatic actuator.

[0114] Alternatively or additionally, one or more actuators of the actuator arrangement may comprise or take the form of an electric actuator.

[0115] According to a second aspect, there is provided a system for use in nondestructive evaluation of an object under test, comprising one or more of the probe apparatus of the first aspect. According to a third aspect, there is provided a method of non-destructive evaluation using the probe apparatus of the first aspect or the system of the second aspect.

[0116] According to a fourth aspect, there is provided a probe apparatus for use in the non-destructive evaluation of an object under test, comprising: a transducer arrangement configured and / or operable to direct an ultrasonic beam towards the object under test; a compliant element configured to engage the object under test; and an intermediate member interposed between the transducer arrangement and the compliant element, wherein the probe apparatus is configured and / or operable and / or is operatively associated with an arrangement to control an angle of inclination of the compliant element so as to reduce a deviation in the ultrasonic beam propagating in the object under test.

[0117] In use, the probe apparatus may be located on an object under test, with the compliant element subjected to a force urging the compliant element into engagement or enhanced engagement with the object under test. The transducer arrangement is configured and / or operable to direct an ultrasonic beam towards the object, with one or more properties of a reflected beam being detected by the transducer arrangement and / or another detection arrangement to determine the properties, condition, integrity and / or behaviour of the object under test. As will be described further below, a fluid is disposed within the probe apparatus, including at the interface between the intermediate member and the compliant element, the fluid acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element and onwards into the object under test. In the present probe apparatus, the probe apparatus is configured and / or operable to control an angle of inclination of the compliant element so as to reduce a deviation in the ultrasonic beam propagating in the object under test.

[0118] It has been found that a 1 degree difference in inclination of the inner and outer surfaces of the compliant element results in a much larger deviation in the ultrasonic beam path inside the object under test. For example, the compliant element often comprises a material through which sound travels at a reduced speed when compared to those materials which the intermediate member and the object under test respectively comprise. Thus, as an ultrasonic beam travels from the intermediate member to the compliant element, the beam is refracted, resulting in a significant change in the angle of the ultrasonic beam. A similar process of refraction occurs as the beam travels from the compliant element to the object under test. Where the inner and outer surfaces of the compliant element are maintained parallel relative to one another, the angle of the ultrasonic beam path inside the object under test remains unaffected.

[0119] Beneficially, the probe apparatus compensates for a deviation in the ultrasonic beam propagating in the object under test resulting from the ultrasonic beam propagating through a compliant element having inner and outer surfaces which are non-parallel.

[0120] As discussed above, the probe apparatus is configured and / or operable and / or is operatively associated with an arrangement to control an angle of inclination of the compliant element so as to reduce a deviation in the ultrasonic beam propagating in the object under test.

[0121] The probe apparatus may be coupled to and / or operatively associated with an active arrangement for controlling the inclination of the compliant element.

[0122] The active arrangement may comprise or take the form of an actuator arrangement.

[0123] The actuator arrangement may comprise one or more actuator.

[0124] One or more actuators of the actuator arrangement may comprise or take the form of a mechanical actuator.

[0125] Alternatively or additionally, one or more actuators of the actuator arrangement may comprise or take the form of a fluid-powered actuator.

[0126] Alternatively or additionally, one or more actuators of the actuator arrangement may comprise or take the form of a robotic actuator, e.g. a robotic arm.

[0127] Alternatively or additionally, one or more actuators of the actuator arrangement may comprise or take the form of a pneumatic actuator. Alternatively or additionally, one or more actuators of the actuator arrangement may comprise or take the form of an electric actuator.

[0128] The probe apparatus may comprise a passive arrangement for controlling the inclination of the compliant element.

[0129] The probe apparatus may comprise a guide arrangement.

[0130] The guide arrangement may be configured and / or operable as a movement limiter.

[0131] The passive arrangement may comprise one or more wheels. The one or more wheels may be configured and / or operable to control the alignment of the compliant element.

[0132] The probe apparatus may comprise, may be coupled to, or operatively associated with a sensor arrangement.

[0133] The sensor arrangement may be configured and / or operable to measure the inclination of the compliant element. The sensor arrangement may be configured and / or operable to measure the inclination of the inner and outer surfaces of the compliant element.

[0134] The sensor arrangement may be configured and / or operable to convey one or more output signals containing measurement data relating to the inclination of the compliant element, e.g. the inclination of the inner and outer surfaces of the compliant element.

[0135] The sensor arrangement may be configured and / or operable to measure the angle of the object under test and / or the angle between the sensor arrangement and the object under test.

[0136] The sensor arrangement may be calibrated according to the position of the object under test. The sensor arrangement may comprise one or more sensors. The sensor arrangement may comprise one or more contactless distance measurement sensors. At least one of the sensors may comprise or take the form of a laser profiler. Alternatively or additionally, at least one of the sensors may comprise or take the form of an IR distance sensor. At least one of the sensors may comprise or take the form of an ultrasonic distance sensor. At least one of the sensors may comprise or take the form of a force sensor. At least one of the sensors may comprise or take the form of a torque sensor.

[0137] The active arrangement may comprise the sensor arrangement. The active arrangement may be configured and / or operable to adapt the inclination of the compliant element according to the reading of the sensor arrangement. The active arrangement may be configured and / or operable to adapt the inclination of the compliant element according to the reading of the sensor arrangement in real-time.

[0138] The sensor arrangement may comprise, may be coupled to, or operatively associated with a communication arrangement for conveying the one or more output signals, e.g. to a control system.

[0139] The communication arrangement may comprise or take the form of a wired communication arrangement. Alternatively, the communication arrangement may comprise or take the form of a wireless communication arrangement.

[0140] The one or more robotic actuators may be configured and / or operable to be controlled by an algorithm. The algorithm may control the one or more robotic actuators based on inclination data produced by the sensor arrangement.

[0141] The intermediate member and the compliant element may be arranged so as to define an interface therebetween. At least one of the intermediate member and the compliant element may be configured and / or operable to retain a fluid disposed at the interface between the intermediate member and the compliant element.

[0142] In use, the probe apparatus may be located on an object under test, with the compliant element subjected to a force urging the compliant element into engagement or enhanced engagement with the object under test. The transducer arrangement is configured and / or operable to direct an ultrasonic beam towards the object, with one or more properties of a reflected beam being detected by the transducer arrangement and / or another detection arrangement to determine the properties, condition, integrity and / or behaviour of the object under test. As will be described further below, a fluid is disposed within the probe apparatus, including at the interface between the intermediate member and the compliant element, the fluid acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element and onwards into the object under test. In the present probe apparatus, one or both of the intermediate member and the compliant element are configured and / or operable to retain the fluid disposed at the interface between the intermediate member and the compliant element.

[0143] As described above, the probe apparatus comprises a transducer arrangement configured and / or operable to direct an ultrasonic beam towards the object under test.

[0144] The transducer arrangement may comprise one or a plurality of transducers. One or more of the transducers may comprise or take the form of a piezoelectric transducer. Alternatively or additionally, one or more of the transducers may comprise or take the form of an eddy current transducer. Alternatively or additionally, one or more of the transducers may comprise or take the form of a capacitive transducer, e.g. a capacitive micro-machined ultrasonic transducer (CMLIT). Alternatively or additionally, one or more of the transducers may comprise or take the form of a dry-coupled ultrasonic test (DCLIT) transducer. Alternatively or additionally, one or more of the transducers may comprise or take the form of an electromagnetic acoustic transducer (EMAT).

[0145] The transducer arrangement may comprise or take the form of a transducer array. The transducer arrangement may comprise one or a plurality of arrays of transducers. In particular, the transducer arrangement may comprise or take the form of a phased array ultrasonic transducer (PALIT) arrangement.

[0146] The transducer arrangement may be configured and / or operable to transmit and / or receive the ultrasonic beam. One or more of the transducers of the transducer arrangement may comprise or take the form of: a transmitter or emitter; a receiver; a transceiver. The transducer arrangement may be coupled to and / or operatively associated with a driver device, for example an ultrasonic driver device. The driver device, for example the ultrasonic driver device, may be configured and / or operable to transmit a pulse. The ultrasonic driver device may be configured and / or operable to transmit an electric pulse. The ultrasonic driver device may be configured and / or operable to transmit a high voltage pulse. The ultrasonic driver device may be configured and / or operable to transmit a high voltage electric pulse. The ultrasonic driver may be configured and / or operable to record a signal which corresponds to the ultrasonic beam received by the one or more receivers.

[0147] In use, the ultrasonic driver device transmits the high voltage electric pulse, causing the one or more transmitters to transmit an ultrasonic beam. The one or more receivers having received the reflected ultrasonic beam, the ultrasonic driver device shall receive a corresponding signal. The ultrasonic driver device shall then record the signal received.

[0148] Alternatively or additionally, the ultrasonic driver device transmits the high voltage electric pulse, causing each of the one or more transmitters to transmit an ultrasonic beam at an interval separate from each of the other transmitters, with the reflections from each of the ultrasonic beams transmitted being received by the one or more receivers. The plurality of receivers having received the reflected ultrasonic beams, the ultrasonic driver device shall receive corresponding signals, which the ultrasonic driver device shall record. Said recorded data may then be utilised in order to conduct advanced reconstruction in order to create a constructive interference in the wavefronts in question.

[0149] The ultrasonic driver device may comprise, may be coupled to and / or operatively associated with a processing system configured to interpret the electronic signal recorded by the ultrasonic driver device following the receipt of the reflected ultrasonic beam by the one or more receivers.

[0150] The processing system, or at least part of the processing system may form part of the ultrasonic driver device. The processing system, or part of the processing system, may be coupled to or operatively associated with the ultrasonic driver device. For example, the processing system may be located at one or more remote location. The remote location may comprise or take the form of a mobile device such as tablet, mobile phone or the like. Alternatively or additionally, the remote location may comprise or take the form of a control room. Alternatively or additionally, the remote location may comprise or take the form of a data store, such as an online data store.

[0151] The ultrasonic driver device may be configured to transmit information to the processing system. The ultrasonic driver device may comprise a communication arrangement configured to communicate the electronic signal corresponding to the ultrasonic beam received by the one or more receivers to one or more remote location. The communication arrangement may comprise or take the form of a two-way communication arrangement.

[0152] As described above, the probe apparatus comprises an intermediate member interposed between the transducer arrangement and the compliant element.

[0153] The intermediate member may comprise or take the form of a solid core.

[0154] The intermediate member may comprise or take the form of a wedge.

[0155] Alternatively, the intermediate member may comprise or take the form of a planar or substantially planar member or may have other shapes.

[0156] The intermediate member may be partially or wholly constructed from a plastic material. The plastic material may comprise or take the form of a thermoplastic material. In particular embodiments, the plastic material may comprise or take the form of polyetherimide, e.g. Ultern®. Alternatively or additionally, the plastic material may comprise or take the form of polyimide, e.g. Vespel®. The plastic material may comprise or take the form of a polyamide-imide, e.g. Duratron®.

[0157] Beneficially, the intermediate member provides high strength and high temperature capabilities, facilitating use in high temperature in-process non-destructive evaluation of objects, such as welds during and / or immediately after the welding process, metal objects during and / or immediately after the metal additive manufacturing process or composite components during and / or immediately after the manufacturing process.

[0158] The transducer arrangement and the intermediate member may together form a transducer assembly of the probe apparatus.

[0159] At least one of the transducer assembly and the compliant element are configured and / or operable to retain a fluid disposed at the interface between the intermediate member and the compliant element.

[0160] As described above, the probe apparatus comprises a compliant element configured for location between the intermediate member and the object under test.

[0161] The compliant element may be partially or wholly constructed from elastomeric material. The elastomeric material may comprise or take the form of a silicone rubber material. In particular embodiments, the compliant element may be partially or wholly constructed from high temperature silicone rubber. Alternatively or additionally, the compliant element may comprise a hydrogenated nitrile butadiene rubber (HNBR) material. The compliant element may comprise an ethylene propylene diene monomer (EPDM) material.

[0162] Beneficially, the compliant element is capable of conforming to the geometry of the object under test and provides high strength and high temperature capabilities, facilitating use in high temperature in-process non-destructive evaluation of objects, such as welds during and / or immediately after the welding process, metal objects during and / or immediately after the metal additive manufacturing process or composite components during and / or immediately after the manufacturing process.

[0163] The compliant element may comprise or take the form of a cylindrical or substantially cylindrical element.

[0164] The probe apparatus may be configured so that the compliant element moves relative to the intermediate member. For example, the probe apparatus may be configured so that the compliant element rotates around the intermediate member and / or the transducer arrangement. In particular embodiments, the compliant element may comprise or take the form of a rolling element. The compliant element may comprise or take the form of a tyre, wheel or the like.

[0165] Alternatively, the compliant element may comprise or take the form of a planar or substantially planar element. For example, the compliant element may comprise or take the form of a membrane.

[0166] The probe apparatus may be configured so that the compliant element moves axially relative to the intermediate member.

[0167] The compliant element may at least partially define an internal volume. The internal volume may comprise or take the form of a chamber. The transducer arrangement and / or the intermediate member (e.g. the transducer assembly) may be disposed within the internal volume.

[0168] The probe apparatus may comprise a support arrangement. The support arrangement may comprise or take the form of a mandrel. In use, the mandrel may form an axle of the probe apparatus.

[0169] The transducer arrangement and / or the intermediate member (e.g. the transducer assembly) may be supported, e.g. mounted, on the mandrel. The transducer arrangement and / or the intermediate member (e.g. the transducer assembly) may be fixedly coupled to, e.g. fixedly mounted on, the mandrel.

[0170] The compliant element may be movably supported, e.g. mounted on or coupled to, the mandrel. In particular embodiments, the compliant element may be rotatably supported, e.g. rotatably mounted on or coupled to, the mandrel. The probe apparatus may comprise a bearing arrangement for rotatably supporting the compliant element.

[0171] As described above, the intermediate member and the compliant element are arranged so as to define an interface therebetween, and at least one of the intermediate member and the compliant element are configured and / or operable to retain the fluid disposed at the interface between the intermediate member and the compliant element. The configuration of the intermediate member and / or the compliant element so as to retain the fluid disposed at the interface may take a number of different forms.

[0172] For example, the configuration of the intermediate member and / or the compliant element so as to retain the fluid disposed at the interface may comprise or take the form of a surface treatment.

[0173] The surface treatment may be formed or otherwise provided on a distal surface of the intermediate member, i.e. the surface of the intermediate member which in use faces the compliant element.

[0174] The surface treatment may comprise or take the form of: one or more protrusions formed or otherwise provided on the intermediate member; one or more ridges formed or otherwise provided on the intermediate member; one or more grooves formed or otherwise provided on the intermediate member; one or more channels formed or otherwise provided on the intermediate member; and / or one or more bores formed or otherwise provided on the intermediate member.

[0175] The surface treatment may be formed by one or more of processes such as: milling, e.g. CNC milling; machining, e.g. laser machining; engraving; etching, e.g. acid etching; and / or sandblasting.

[0176] The one or more of processes may be applied to the intermediate member and / or to the mould used to form the intermediate member.

[0177] The surface roughness of the intermediate member may be selected based on the frequency and / or wavelength of the ultrasonic beam.

[0178] For example, the surface roughness may be selected to be:

[0179] Ra < A / 10, Where Ra is surface roughness Where A is wavelength.

[0180] Beneficially, this may minimise or at least reduce wavefront aberration.

[0181] Alternatively or additionally, the surface treatment may be formed or otherwise provided on a surface of the compliant element which faces the intermediate member, which in use may be an upper surface or internal surface of the compliant element.

[0182] The surface treatment may comprise or take the form of: one or more protrusions formed or otherwise provided on the compliant element; one or more ridges formed or otherwise provided on the compliant element; one or more grooves formed or otherwise provided on the compliant element; one or more channels formed or otherwise provided on the compliant element; and / or one or more bores formed or otherwise provided on the compliant element.

[0183] The surface treatment may be formed by one or more of processes such as: milling, e.g. CNC milling; machining, e.g. laser machining; engraving; etching, e.g. acid etching; and / or sandblasting.

[0184] The one or more of processes may be applied to the compliant element and / or to the mould used to form the compliant element.

[0185] The surface roughness of the compliant element may be selected based on the frequency and / or wavelength of the ultrasonic beam.

[0186] For example, the surface roughness may be selected to be:

[0187] Ra < A / 10, Where Ra is surface roughness Where A is wavelength.

[0188] Beneficially, this may minimise or at least reduce wavefront aberration.

[0189] As described above, in use, the probe apparatus may be located on an object under test, with the compliant element subjected to a force urging the compliant element into engagement or enhanced engagement with the object under test. The transducer arrangement is configured and / or operable to direct an ultrasonic beam towards the object, with one or more properties of a reflected beam being detected by the transducer arrangement and / or another detection arrangement to determine the properties, condition, integrity and / or behaviour of the object under test. As will be described further below, a fluid is disposed within the probe apparatus, including at the interface between the intermediate member and the compliant element, the fluid acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element and onwards into the object under test. In the present probe apparatus, one or both of the intermediate member and the compliant element are configured and / or operable to retain the fluid disposed at the interface between the intermediate member and the compliant element.

[0190] In some embodiments, the intermediate member and the compliant element may be reconfigurable from a first configuration in which the intermediate member and the compliant element are spaced from each other to a second configuration, e.g. in response to the applied load, in which the intermediate member engages the compliant element and which prevents the fluid in the interface from escaping.

[0191] Alternatively, the intermediate member and the compliant element may be arranged so as to always be engaged, the intermediate member and the compliant element being reconfigurable from a first configuration in which the intermediate member and the compliant element are engaged but which permit fluid in the interface to escape and a second configuration, e.g. in response to the applied load, in which the intermediate member engages the compliant element and which prevents the fluid in the interface from escaping. The probe apparatus may be reconfigurable from a first configuration, in which the distal surface and the internal surface are separate, to a second configuration, in which the distal surface engages the internal surface, the one or more protrusions of the distal surface and / or the internal surface respectively retaining a fluid in position at an interface formed by the engagement of the distal surface and the internal surface.

[0192] The probe apparatus may comprise an absorber.

[0193] The absorber may be coupled to and / or operatively associated with the intermediate member. The absorber may be coupled to and / or operatively associated with an external wall of the intermediate member, i.e. the surface of the intermediate member which, in use, is positioned vertically or substantially vertically.

[0194] The absorber is configured and / or operable to absorb ultrasonic waves.

[0195] Beneficially, the absorber may prevent undesired reflected waves / signals affecting the evaluation.

[0196] As described above, a fluid is disposed within the probe apparatus, including at the interface between the intermediate member and the compliant element, the fluid acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element and onwards into the object under test. In the present probe apparatus, one or both of the intermediate member and the compliant element are configured and / or operable to retain the fluid disposed at the interface between the intermediate member and the compliant element.

[0197] The probe apparatus may comprise an inlet arrangement. The inlet arrangement may comprise one or more inlets.

[0198] The probe apparatus may comprise an outlet arrangement. The outlet arrangement may comprise one or more outlets.

[0199] The inlet arrangement may be coupled to and / or operatively associated with a fluid arrangement. The fluid arrangement may be configured and / or operable to supply the fluid for disposal at the interface between the intermediate member and the compliant element. The fluid arrangement may be configured and / or operable to supply the fluid for disposal at the interface via the inlet arrangement.

[0200] The outlet arrangement may be coupled to and / or operatively associated with the fluid arrangement. The fluid arrangement may be configured and / or operable to remove the fluid from the interface. The fluid arrangement may be configured and / or operable to remove the fluid from the interface via the outlet arrangement.

[0201] The fluid arrangement may be configured and / or operable to supply the fluid for disposal at the interface via the outlet arrangement.

[0202] The fluid arrangement may be configured and / or operable to remove the fluid from the interface via the inlet arrangement.

[0203] The fluid arrangement may be configured and / or operable to simultaneously supply and remove the fluid.

[0204] The fluid arrangement may be configured and / or operable to sequentially supply and remove the fluid.

[0205] The inlet arrangement and the outlet arrangement may comprise or take the form of separate arrangements.

[0206] Alternatively, e.g. where the fluid arrangement is configured and / or operable to supply and then remove the fluid sequentially, the inlet arrangement and the outlet arrangement may comprise the same arrangement.

[0207] The apparatus may comprise a valve arrangement. The valve arrangement may be configured and / or operable to control ingress and / or egress of the fluid.

[0208] The fluid arrangement may comprise, be coupled to and / or operatively associated with a cooling arrangement. The cooling arrangement may be configured and / or operable to cool the fluid for disposal at the interface. In use, the cooling arrangement cools the fluid for disposal at the interface between the intermediate member and the compliant element. The fluid source subsequently supplies the fluid to the internal volume of the compliant element via the inlet arrangement, at which point the fluid becomes disposed at the interface. The fluid, having undergone an increase in temperature through use of the probe apparatus, is then removed by the fluid arrangement from the internal volume of the compliant element via the outlet arrangement. Whilst removing the high temperature fluid from the internal volume, the fluid arrangement may simultaneously supply fluid which has been cooled via the cooling arrangement to the internal volume, in order to replace the high temperature fluid removed. The cooling arrangement then cools the high temperature fluid removed, which may then be resupplied to the internal volume of the compliant element via the inlet arrangement.

[0209] The fluid may be configured and / or operable to act as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element and onwards into the object under test.

[0210] The fluid may comprise or take the form of a liquid.

[0211] The fluid may comprise or take the form of a coolant.

[0212] The fluid may comprise or take the form of a couplant.

[0213] According to a fifth aspect, there is provided a system for use in non-destructive evaluation of an object under test, comprising one or more of the probe apparatus of the fourth aspect.

[0214] The system may comprise an arrangement. The arrangement may be configured and / or operable to control an angle of inclination of the compliant element so as to reduce a deviation in the ultrasonic beam propagating in the object under test. The arrangement may comprise or take the form of an active arrangement.

[0215] The system may comprise, may be coupled to or operatively associated with a control system. Amongst other things, the control system may be configured and / or operable to control the inclination of the compliant element. The control system may be configured to receive the one or more output signals from the sensor arrangement. The one or more output signals from the sensor arrangement may form an input to a position control algorithm under the control of the control system. The one or more output signals from the sensor arrangement may form an input to an imaging compensation algorithm under the control of the control system.

[0216] According to a sixth aspect, there is provided a method of non-destructive evaluation using the probe apparatus of the fourth aspect or the system of the fifth aspect.

[0217] According to a seventh aspect, there is provided a probe apparatus for use in the non-destructive evaluation of an object under test, wherein the probe apparatus comprises or takes the form of a roller probe, the probe apparatus comprising: a transducer assembly, wherein the transducer assembly comprises or takes the form of a transmit receive longitudinal (TRL) arrangement.

[0218] The probe apparatus may comprise a transducer arrangement. The transducer arrangement may be configured and / or operable to direct an ultrasonic beam towards the object under test. The transducer arrangement may comprise one or a plurality of transducers.

[0219] The probe apparatus may comprise a compliant element. The compliant element may be configured to engage the object under test. The compliant element may comprise or take the form of a rolling element. The compliant element may comprise or take the form of a tyre, wheel or the like. For example, the probe apparatus may comprise or take the form of a roller probe, as discussed above.

[0220] The probe apparatus may comprise one or a plurality or intermediate members. The one or the plurality of intermediate members may be interposed between the transducer arrangement and the compliant element.

[0221] The transducer arrangement and the one or the plurality of intermediate members may together form the transducer assembly of the probe apparatus. As discussed above, the transducer assembly may comprise or take the form of a transmit receive longitudinal (TRL) arrangement.

[0222] At least one of the plurality of intermediate members may be angled.

[0223] In use, each of the plurality of intermediate members are angled such that the ultrasonic beams transmitted by the plurality of transducers of the transducer arrangement may converge at a focal point.

[0224] According to an eighth aspect, there is provided a probe apparatus for use in the non-destructive evaluation of an object under test, comprising: a transducer arrangement configured and / or operable to direct an ultrasonic beam towards the object under test, wherein the probe apparatus comprises or takes the form of a roller probe; and wherein the transducer arrangement comprises or takes the form of a matrix array.

[0225] The transducer arrangement may comprise one or a plurality of transducers. The transducer arrangement may comprise or take the form of a matrix array, as discussed above.

[0226] The probe apparatus may comprise a compliant element. The compliant element may be configured to engage the object under test. The compliant element may comprise or take the form of a rolling element. The compliant element may comprise or take the form of a tyre, wheel or the like. For example, the probe apparatus may comprise or take the form of a roller probe, as discussed above.

[0227] The probe apparatus may comprise an intermediate member. The intermediate member may be interposed between the transducer arrangement and the compliant element.

[0228] According to a ninth aspect, there is provided a method for non-destructive evaluation of an object under test, wherein the object under test comprises or takes the form of a non-welded construction, the method comprising: emitting ultrasound into the object under test and receiving ultrasound back from the object under test, thereby acquiring multiple signal sets, including a first signal set and a second signal set; processing the first signal set and the second signal set to provide evaluation data relating to the object under test, wherein the first signal set comprises a first series of first data elements, the first series of data elements spanning a first time period, each first data element including a first variable value for a variable and a first time value for that first variable value, the first time period including a first time sub-period; the second signal set comprises a second series of second data elements, the second series of second data elements spanning a second time period, each second data element including a second variable value for the variable and a second time value for that second variable value, the second time period including a second time sub-period; the first time sub-period and the second time sub-period cover the same time values; the processing of the first signal set and the second signal set determining a modified signal set which contributes to the evaluation data, wherein the modified signal set: includes a modified time sub-period covering the same time values as the first time sub-period and the second time sub-period; and includes, for a time value, an expression of the first variable value for that time value and an expression of the second variable value for that time value, if the first variable value and the second variable value are within a given relationship to one another; and / or includes, for a time value, one of an expression of the first variable value for that time value or an expression of the second variable value for that time value, if the first variable value and the second variable value are not within a given relationship to one another. The method may comprise the preliminary step of providing a probe apparatus and disposing the probe apparatus relative to the object under test so as to permit the probe apparatus to_emit ultrasound into the object under test and receive ultrasound back from the object under test. The method may comprise locating the probe apparatus in proximity to the object under test. The method may comprise locating the probe apparatusjn contact with the object under test. The method may comprise locating the probe apparatus adjacent to_the object under test without contacting the object under test.

[0229] The object under test may takes a variety of different forms.

[0230] For example, the object under test may comprise or take the form of an object constructed using additive manufacturing techniques. In particular, the object under test may comprise or take the form of an object constructed using metal additive manufacturing, such as but not limited to wire arc additive manufacturing (WAAM).

[0231] Metal additive manufacturing is a method of metal production which involves the addition of numerous layers in succession in order to produce a metal object. Metal additive manufacturing is a method unlike its subtractive counterparts, which form metal parts via the removal of material, or the shaping of material via machining, milling or forming, for example.

[0232] The method may thus be defined as a method for use in the non-destructive evaluation of an object constructed using additive manufacturing techniques. The method may thus be further defined as a method for use in the non-destructive evaluation of an object constructed using metal additive manufacturing techniques, such as but not limited to wire arc additive manufacturing (WAAM).

[0233] Alternatively, the object under test may comprise or take the form of an object constructed from a composite material.

[0234] The method may thus be defined as a method for use in the non-destructive evaluation of an object constructed from a composite material. Alternatively, the object under test may comprise or take the form of the human or animal body.

[0235] The method may thus be defined as a method for use in the non-invasive evaluation of the human or animal body. The method may be further defined as a method for use in the therapeutic or non-therapeutic non-invasive evaluation of the human or animal body.

[0236] The first variable value may be an expression of amplitude, for instance at a given time value, particularly the amplitude of the rectified signal set.

[0237] The second variable value may be an expression of amplitude, for instance at a given time value, particularly the amplitude of the rectified signal set.

[0238] The first time period, second time period and / or one or more further time periods may be the same duration. The first time period, second time period and / or one or more further time periods may be the same duration + / - 25%. The first time period, second time period and one or more further time periods may be the duration of the receiver signal for an ultrasound beam or wave. The first time subperiod and / or the second time sub-period and / or one or more further sub-time periods may be individual time values. The first time sub-period and / or the second time sub-period and / or one or more further sub-time periods may be small sets of individual time values.

[0239] The first time period may be considered as multiple different or partially overlapping first time sub-periods. The second time period may be considered as multiple different or partially overlapping second time sub-periods. The further time period may be considered as multiple different or partially overlapping further time sub-periods. The multiple time sub-periods may be paired with one another when they are for the same time values. The modified signal set may be complied from the consideration of a number of time sub-periods according to the method.

[0240] The method may provide that, in the modified signal set, the expression of the first variable value for that time value and the expression of the second variable value for that time value may be an average of the first variable value and the second variable value. The method may provide that, in the modified signal set, the expression of the first variable value for that time value and / or the expression of the second variable value for that time value, together with a further variable value may be an average of all the variable values within a given relationship.

[0241] The method may provide that the first variable value and the second variable value are within a given relationship to one another, if the first variable value and the second variable value are within a given threshold. The nature and / or defining function and / or value of the given threshold may be variable. The threshold may vary, particularly increase, where system gain increases and / or where noise increases in the signal sets. The threshold may vary, particularly increase, where interference levels increase in the signal sets. The nature and / or defining function and / or value of the threshold may be determined in a calibration method.

[0242] The method may provide that the first variable value and the second variable value are not within a given relationship to one another, if the first variable value and the second variable value are outside a further given threshold, potentially the same threshold. The nature and / or defining function and / or value of the given threshold may be variable. The further given threshold may vary, particularly increase, where system gain increases and / or where noise increases in the signal sets. The further given threshold may vary, particularly increase, where interference levels increase in the signal sets.

[0243] The method may further provide that where the first variable value and the second variable value are not within a given relationship to one another, that the included one expression, chosen from the first and the second, be the expression with the lower variable value for that time value. The method may further provide that where a variable value and the compared variable value are not within a given relationship to one another, that the included one expression be the expression with the lower variable value for that time value. The lower variable value may be the lower variable value considered absolute terms.

[0244] The given threshold may be determined relative to an amplitude for the first and second variable value.

[0245] The amplitude may be a pre-determined amplitude value. The amplitude may be an anticipated amplitude value, for instance relative to an anticipated noise amplitude. The amplitude may be a defined proportion or multiple of the anticipated noise amplitude.

[0246] The amplitude may be an observed amplitude. The amplitude may relate to the maximum amplitude observed in a set of variable values deemed free of interference.

[0247] The amplitude may relate to the minimum value observed for a time or time period across all of the sets of variable values being considered, for instance across the first variable values, second variable values and one or more further variable values. The amplitude may be the minimum plus a factor. This amplitude may be deemed an interference free threshold.

[0248] The threshold may be a difference between an observed value and an analysis value. The observed value and the analysis values may be amplitudes. The analysis value may be obtained from the minimum value observed for a time or time period across all of the sets of variable values being considered, for instance across the first variable values, second variable values and one or more further variable values. The analysis value may be the minimum plus a factor.

[0249] The method may further include acquiring one or more further signal sets as part of the multiple signal sets.

[0250] The method may further include processing one or more of the further signal sets to provide evaluation data.

[0251] The method may further include one or more or all of the further signal sets comprising a further series of further data elements, each further series of further data elements may span a further time period, each further data element including a further variable value for the variable and a further time value for that further variable value, each further time period including a further time sub-period.

[0252] The method may further include, one of the further time sub-periods covering the same time values as at least one of the first time sub-period and / or the second time sub-period.

[0253] The method may further include the processing of one or more or all of the further signal sets determining a modified signal set which contributes to the evaluation data. The method may further include the modified signal set spanning a modified time sub-period covering the same time values as a further time sub period and one or both of the first time subperiod and the second time sub-period.

[0254] The method may further include the modified signal set including, for a time value, an expression of the first variable value for that time value and an expression of the second variable value for that time value and an expression of one of the further variable values for that time value, if the first variable value and the second variable value and the further variable value are within a given relationship to one another.

[0255] The method may, alternatively or additionally include the modified signal set including, for a time value, one of an expression of the first variable value for that time value or an expression of the second variable value for that time value or an expression of the further variable value, if the first variable value and the second variable value and third variable value are not within a given relationship to one another.

[0256] The method may, alternatively or additionally, may further include the modified signal set including, for a time value, two of: an expression of the first variable value for that time value; an expression of the second variable value for that time value; an expression of one of the further variable values for that time value; for the two variable values that are within a given relationship to one another.

[0257] The method may, alternatively or additionally, may further include the modified signal set including, for a time value, only one of the: an expression of the first variable value for that time value; an expression of the second variable value for that time value; an expression of one of the further variable values for that time value; where the variable values are not within a given relationship to one another.

[0258] The method may further provide that the modified signal set is compiled from multiple modified time sub-periods, each covering the same time values as a first time sub-period and / or second time sub-period and / or one or more further time sub-periods. According to a tenth aspect, there is provided a method for non-destructive evaluation of an object under test, wherein the object under test comprises or takes the form of non-welded construction, the method comprising: conducting the evaluation, wherein the object under test is provided at an elevated temperature state above ambient temperature by heating during the evaluation, the conducting of the evaluation comprising: emitting an ultrasound wave into a volume of the object under test; receiving at least a part of the ultrasound wave back from the object under test, thereby acquiring multiple signal sets; and processing one or more of the multiple signal sets to provide evaluation data relating to the object under test, wherein the processing includes a correction for temperature within the volume of the object under test at the elevated temperature.

[0259] The method may comprise the preliminary step of providing a probe apparatus and disposing the probe apparatus relative to the object under test so as to permit the probe apparatus to emit ultrasound into the object under test and receive ultrasound back from the object under test. The method may comprise locating the probe apparatus in proximity to the object under test. The method may comprise locating the probe apparatus in contact with the object under test. The method may comprise locating the probe apparatus adjacent to the object under test without contacting the object under test.

[0260] The object under test may takes a variety of different forms.

[0261] For example, the object under test may comprise or take the form of an object constructed using additive manufacturing techniques. In particular, the object under test may comprise or take the form of an object constructed using metal additive manufacturing, such as but not limited to wire arc additive manufacturing (WAAM).

[0262] Metal additive manufacturing is a method of metal production which involves the addition of numerous layers in succession in order to produce a metal object. Metal additive manufacturing is a method unlike its subtractive counterparts, which form metal parts via the removal of material, or the shaping of material via machining, milling or forming, for example.

[0263] The method may thus be defined as a method for use in the non-destructive evaluation of an object constructed using additive manufacturing techniques. The method may thus be further defined as a method for use in the non-destructive evaluation of an object constructed using metal additive manufacturing techniques, such as but not limited to wire arc additive manufacturing (WAAM).

[0264] Alternatively, the object under test may comprise or take the form of an object constructed from a composite material.

[0265] The method may thus be defined as a method for use in the non-destructive evaluation of an object constructed from a composite material.

[0266] The method may include an elevated temperature which is consistent through the object under test and / or an elevated temperature which includes a temperature distribution, such as a temperature gradient, in the object under test and / or probe apparatus.

[0267] The processing includes a correction for temperature distribution, for instance temperature gradient, within the volume of the object under test at the elevated temperature.

[0268] The method may provide that the correction includes, the path of at least a part of the ultrasound wave through probe apparatus and / or the volume of the object under test being corrected to give a corrected path.

[0269] The method may provide that the part of the ultrasound wave has path characteristics in one or more elements that the path passes through. The method may provide that the part of the ultrasound wave in the probe apparatus has path characteristics in one or more media elements. The method may provide that the part of the ultrasound wave in the substrate has path characteristics in one or more substrate elements. The method may provide that the part of the ultrasound wave in the object under test has path characteristics in one or more objectelements. The method may provide that the part of the ultrasound wave in the interface between the probe apparatus and the substrate has path characteristics in one or more interface elements.

[0270] The ultrasound wave may have path characteristics in each of a plurality of elements, for instance each element adjoining a predecessor element and a successor element. The ultrasound wave may have path characteristics in each of one or more media elements. The ultrasound wave may have path characteristics in each of one or more interface elements. The ultrasound wave may have path characteristics in each of one or more substrate elements. The ultrasound wave may have path characteristics in each of the one or more object elements.

[0271] The ultrasound wave may have path characteristics in each of one or more media elements, followed by path characteristics in each of one or more substrate elements. The ultrasound wave may have path characteristics in each of one or more interface elements, for instance after the media elements and / or before the substrate elements. The ultrasound wave may have path characteristics in each of one or more weld elements, for instance after the substrate elements.

[0272] The ultrasound wave may further, for instance in a return path, have path characteristics in each of one or more substrate elements, followed by path characteristics in each of one or more media elements. The ultrasound wave may have path characteristics in each of one or more objectelements, for instance before the substrate elements. The ultrasound wave may have path characteristics in each of one or more interface elements, for instance after the substrate elements and / or before the media elements.

[0273] The method may provide that the part of the ultrasound wave has path characteristics in the probe apparatus element, for instance in a media element, and / or has path characteristics in the interface, for instance in an interface element, before the part of the ultrasound wave enters a first element of the substrate, for instance a first substrate element. The method may provide that the first element has a temperature within the temperature distribution, such as temperature gradient, for the volume of the substrate and / or weld, with temperature-corrected path characteristics being determined for the part of the ultrasound wave in the first element, the temperature-corrected path characteristics being based upon the change in temperature between the weld inspection apparatus element, for instance a media element and / or an interface element, and the first element of the substrate, for instance a first substrate element.

[0274] The change in the path characteristics may be calculated according to Snell’s Law of Refraction.

[0275] The method may provide that the part of the ultrasound wave has path characteristics in a first element of the substrate, for instance a first substrate element, before the part of the ultrasound wave enters a second element of the substrate, for instance a second substrate element. The method may further provide that the first element has a temperature within the temperature distribution, such as temperature gradient, for the volume of the substrate and / or weld, the second element has a temperature within the temperature distribution, such as temperature gradient, for the volume of the substrate and / or weld, with the temperature-corrected path characteristics being determined for the part of the ultrasound wave in the second element, for instance second substrate element, the temperature-corrected path characteristics being based upon the change in temperature between the first element and the second element, such as between the first substrate element and the second substrate element.

[0276] The method may provide that the part of the ultrasound wave has path characteristics in a first further element of the substrate, for instance a first further substrate element, before the part of the ultrasound wave enters a second further element of the substrate, for instance a second further substrate element. The method may further provide that the first further element has a temperature within the temperature distribution, such as temperature gradient, for the volume of the substrate and / or object under test, the second further element has a temperature within the temperature distribution, such as temperature gradient, for the volume of the substrate and / or object under test, with the temperature-corrected path characteristics being determined for the part of the ultrasound wave in the second further element, for instance second further substrate element, the temperature- corrected path characteristics being based upon the change in temperature between the first further element and the second further element, such as between the first further substrate element and the second further substrate element.

[0277] The method may provide that the temperature-corrected path characteristics are determined for each element that the part of the ultrasound wave passes through in probe apparatus and / or the substrate and / or the object under test, for instance for each element passed through in the weld inspection apparatus and / or substrate and / or object under test.

[0278] The method may provide that the change in temperature is expressed as a change in the speed of sound between the speed of sound in one element and the speed of sound in the next element.

[0279] The method may provide that a plurality of different parts of the ultrasound wave in the weld inspection apparatus and / or in the volume of the substrate and / or in the object under test are corrected to give a corrected path, for instance all of the way through the weld inspection apparatus and / or substrate and / or object under test.

[0280] The method may provide for a plurality of corrected paths, for instance all of the way through the probe apparatus and / or substrate and / or object under test and / or back again. The method may provide at least 5 corrected paths, possibly at least 15 corrected paths, potentially at least 25 corrected paths and optionally at least 40 corrected paths, such as 64 corrected paths.

[0281] A corrected path may be provided for the path of each beam of ultrasound emitted by the transducer, for instance a 64-element phased array.

[0282] The method may provide that a region of interest is selected, the region of interest being within the volume of the substrate and object under test that the ultrasound wave has passed through, the region of interest being sub-divided into locations, such as pixels. The method may apply a signal correction for a location, such as a pixel. The method may apply a signal correction for each location, such as each pixel, in the region of interest, the beam path to the location, such as a pixel, and / or to the return beam path. The method may provide that the signal correction is determined according to a relationship between a location, such as a pixel, and at least one, preferably at least a pair, of the corrected paths. The relationship may be a geometric relationship. The relationship may be a weighted correction based upon the relative geometric position to the one or more corrected paths.

[0283] The method may provide that the signal correction is determined according to a relationship between a location, such as a pixel, and at least one, preferably at least a pair, of positions on at least one, preferably at least a pair, of the corrected paths. The relationship may be a geometric relationship. The relationship may be a weighted correction based upon the relative geometric position, such as distance, between the location and at least one, preferably at least a pair, of positions on at least one, preferably at least a pair, of the corrected paths.

[0284] The method may include a signal correction for one or more locations, such as pixels, that a corrected path for an emitted ultrasound beam passes through. The signal correction may be predominantly or exclusively based upon the corrected path for the emitted ultrasound beam that passes through the location, such as pixel. The signal correction may be based upon a relationship which is a weighted correction based upon the relative geometric position, such as distance, between the location and at least one, preferably at least a pair, of positions on at least one, preferably at least a pair, of the corrected paths, with the signal correction potentially predominantly or exclusively based upon the corrected path for the emitted ultrasound beam that passes through the location, such as pixel.

[0285] The method may include a signal correction for one or more locations, such as pixels, that a corrected path for an emitted ultrasound beam does not pass through. The method may include a signal correction for a location, such as a pixel, that a corrected path for an emitted beam does not pass through, based upon the calculated or observed correction for a location that a corrected path for an emitted beam does pass through. The signal correction may be based upon the calculated or observed position for a plurality, for instance four, locations that an emitted beam has passed through. The signal correction may be based upon the calculated or observed position for a plurality of locations on a first emitted beam and a plurality of locations on a second emitted beam. The first and second emitted beams may be adjacent beams in a set of beams. The first beam may be to one side of the location requiring signal correction and the second beam may be to the other side of the location requiring signal correction.

[0286] The signal correction for a location may be a weighted combination of the signal correction for one or more other locations, for instance one or more other locations that an emitted beam has passed through. The weighted combination may be based upon four locations. The weighted combination may be based upon two locations on one beam and two locations on another beam.

[0287] The signal correction for a location may be weighted according to the fraction of the distance, between a location on the first beam and a location on the second beam, that the location occurs at. The signal correction for a location may be weighted according to a ratio of the distance that location is from a location on the first beam and the distance that location is from a location of the second beam, for instance weighting the corrections from those locations. The distance may be considered along an arc an equal distance from the transducer that passes through the first beam, the location to be corrected and the second beam.

[0288] The signal correction for a location may be weighted according to the fraction of the distance, between a first location on the first beam and a second location on the first beam, that the location occurs at. The signal correction for a location may be weighted according to a ratio of the distance that location is from a first location on the first beam and the distance that location is from a second location of the first beam, for instance weighting the corrections from those locations. The distance may be considered along the first beam. The distance values for each location, such as a pixel, in the region of interest or even in the substrate, may be pre-calculated and stored.

[0289] The acoustic velocity in each location, such as pixel, in the region of interest or even the substrate, may be calculated. The beam path through each boundary between locations, such as pixels, in the region of interest or even the substrate, may be calculated, for instance according to Snell’s Law of Refraction.

[0290] The temperature may be mapped for each location, such as pixel, in the region of interest or even the substrate. The region of interest or even the substrate may be allocated temperature contours, for instance perpendicular to a surface of the substrate.

[0291] The method may include determining the transit time though each location, for instance, determined by the distance and velocity in the zone. The method may establish the net transit time as the sum of the transit times through all the locations on a path.

[0292] The method may provide that the results set includes one or more measured indications of geometry of the substrate and / or object groove and / or object, wherein the method further includes a comparison of the measured indications of geometry with a modelled indications of geometry, wherein if the comparing of the measured indications of geometry with the modelled indications of geometry establishes that the measured indications of geometry is a sufficient fit for the modelled indications of geometry, accepting the imaging of the region of interest.

[0293] The method may provide that the results set includes one or more measured indications of geometry of the substrate and / or object groove and / or weld, wherein the method further includes a comparison of the measured indications of geometry with a modelled indications of geometry, wherein if the comparing of the measured indications of geometry with the modelled indications of geometry establishes that the measured indications of geometry is an insufficient fit for the modelled indications of geometry, the temperature distribution used in the correction for temperature distribution within the volume of the substrate and / or the weld, at the elevated temperature is predetermined.

[0294] The method may provide that the method includes providing a thermal model and generating, using the thermal model, a modelled temperature distribution position for at least a part of the substrate, with the elevated temperature state, the part of the substrate including the volume. The method may provide that the method includes measuring the temperature at a plurality of locations, with the substrate at the elevated temperature, to obtain a measured temperature distribution position, the method further including comparing the measured temperature distribution position with the modelled temperature distribution position. The method may provide that the method further includes, if the comparing of the measured temperature distribution position with the modelled temperature distribution position establishes that the modelled temperature distribution is an insufficient fit for the measured temperature distribution, revising the thermal model and / or the modelled temperature distribution position and then re-comparing.

[0295] The method may provide that the method further includes, if the comparing of the measured temperature distribution position with the modelled temperature distribution position establishes that the modelled temperature distribution is a sufficient fit for the measured temperature distribution, calculating a characteristic of the emitted ultrasound during transit of at least a part of the substrate and / or object under test.

[0296] According to a eleventh aspect, there is provided a method for nondestructive evaluation of an object under test,, wherein the object under test comprises or takes the form of non-welded construction the method including: providing an ultrasound probe comprising: an axial element; an ultrasound emitting transducer mounted on the axial element; two or more support elements rotatable mounted relative to the axial element; a compliant element, the compliant element being mounted on the two or more support elements and providing a continuous surface in at least one direction; wherein the two or more support elements and the compliant element at least partially define an internal volume for the probe, the transducer being provided within the internal volume; the probe further comprising an inlet for coolant to the internal volume and an outlet for coolant from the internal volume; the method further providing: placing at least a section of the compliant element in contact with the object under test; passing ultrasound from the transducer into the object under test and detecting ultrasound returns from the substrate, wherein coolant is fed into the internal volume via the coolant inlet and coolant is removed from the internal volume during the passing of ultrasound.

[0297] The method may comprise the preliminary step of providing a probe apparatus and disposing the probe apparatus relative to the object under test so as to permit the probe apparatus to emit ultrasound into the object under test and receive ultrasound back from the object under test. The method may comprise locating the probe apparatus in proximity to the object under test. The method may comprise locating the probe apparatus in contact with the object under test. The method may comprise locating the probe apparatus adjacent to the object under test without contacting the object under test.

[0298] The object under test may takes a variety of different forms.

[0299] For example, the object under test may comprise or take the form of an object constructed using additive manufacturing techniques. In particular, the object under test may comprise or take the form of an object constructed using metal additive manufacturing, such as but not limited to wire arc additive manufacturing (WAAM).

[0300] Metal additive manufacturing is a method of metal production which involves the addition of numerous layers in succession in order to produce a metal object. Metal additive manufacturing is a method unlike its subtractive counterparts, which form metal parts via the removal of material, or the shaping of material via machining, milling or forming, for example.

[0301] The method may thus be defined as a method for use in the non-destructive evaluation of an object constructed using additive manufacturing techniques. The method may thus be further defined as a method for use in the non-destructive evaluation of an object constructed using metal additive manufacturing techniques, such as but not limited to wire arc additive manufacturing (WAAM). Alternatively, the object under test may comprise or take the form of an object constructed from a composite material.

[0302] The method may thus be defined as a method for use in the non-destructive evaluation of an object constructed from a composite material.

[0303] The method may provide that the temperature of the object under test at the location contacted by the section of the compliant element has a temperature of at least 250°C. The method may provide that the temperature of the object under test at the location contacted by the section of the compliant element has a temperature of at least 300°C.

[0304] The method may include the probe being rolled across the object under test, for instance, such that different sections of the compliant element contact the object under test at different locations on the object under test.

[0305] The method may include pumping the coolant into and / or out of the probe apparatus.

[0306] The method may include cooling the coolant outside of the probe apparatus. The method may include cooling the coolant using a heat exchanger.

[0307] The method may include returning coolant to the internal volume multiple times.

[0308] According to another aspect, there is provided a computer program product configured such that when processed by a suitable processing system the computer program product configures the processing system to implement one or more of the previous aspects.

[0309] The computer program product may be provided on or comprised in a carrier medium. The carrier medium may be transient or non-transient. The carrier medium may be tangible or non-tangible. The carrier medium may comprise a signal such as an electromagnetic or electronic signal. The carrier medium may comprise a physical medium, such as a disk, a memory card, a memory, and / or the like. According to another aspect, there is provided a carrier medium, the carrier medium comprising a signal, the signal when processed by a suitable processing system causes the processing system to implement one or more of the previous aspects.

[0310] It will be well understood by persons of ordinary skill in the art that whilst some embodiments may implement certain functionality by means of a computer program having computer-readable instructions that are executable to perform the method of the embodiments. The computer program functionality could be implemented in hardware (for example by means of a CPU or by one or more ASICs (application specific integrated circuits) or by one or more FPGAs (field programmable gate arrays)) or by a mix of hardware and software.

[0311] Whilst particular pieces of apparatus have been described herein, in alternative embodiments, functionality of one or more of those pieces of apparatus can be provided by a single unit, processing resource or other component, or functionality provided by a single unit can be provided by two or more units or other components in combination. For example, one or more functions of the processing system may be performed by a single processing device, such as a personal computer or the like, or one or more or each function may be performed in a distributed manner by a plurality of processing devices, which may be locally connected or remotely distributed.

[0312] The invention is defined by the appended claims. However, for the purposes of the present disclosure it will be understood that any of the features defined above or described below may be utilised in isolation or in combination. For example, features described above in relation to one of the above aspects or below in relation to the detailed description may be utilised in any other aspect, or together to form a new aspect.

[0313] BRIEF DESCRIPTION OF DRAWINGS

[0314] These and other aspects will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0315] Figure 1 shows a diagrammatic view of a probe apparatus, generally denoted 10, for use in the non-destructive evaluation of an object under test W;

[0316] Figure 2 shows a diagrammatic view of the probe apparatus shown in Figure 1 , with compliant element removed;

[0317] Figure 3 shows a cross-sectional view of the probe apparatus shown in Figure 1 ;

[0318] Figure 4 shows a diagrammatic view of the transducer arrangement and intermediate member of the probe apparatus shown in Figure 1 ;

[0319] Figures 5A to 5D show surface treatments;

[0320] Figure 6 shows a diagrammatic view of a system for use in non-destructive evaluation of an object under test, comprising the probe apparatus shown in Figure 1 ;

[0321] Figure 7 shows a diagrammatic view of an alternative probe apparatus;

[0322] Figure 8 shows a diagrammatic view of a probe apparatus, generally denoted 110, for use in the non-destructive evaluation of an object under test W;

[0323] Figure 9 shows a diagrammatic view of the probe apparatus shown in Figure 8, with compliant element removed;

[0324] Figure 10 shows a cross-sectional view of the probe apparatus shown in Figure 8;

[0325] Figure 11 shows a diagrammatic view of the transducer arrangement and intermediate member of the probe apparatus shown in Figure 8;

[0326] Figures 12A to 12D show surface treatments;

[0327] Figure 13 shows a diagrammatic view of a system for use in non-destructive evaluation of an object under test, comprising the probe apparatus shown in Figure 8;

[0328] Figure 14 shows a graph illustrating error propagation due to angle deviation;

[0329] Figure 15 shows a graph of parametric analysis of beam angle error for a variety of angles of the compliant element vs intended ultrasonic beam angle;

[0330] Figure 16 shows a diagrammatic view of an alternative probe apparatus;

[0331] Figure 17 shows a diagrammatic view of the transducer arrangement and intermediate member of an alternative probe apparatus;

[0332] Figure 18 shows a cross-sectional view of the transducer arrangement and intermediate member of an alternative probe apparatus;

[0333] Figure 19 shows a perspective view of the transducer arrangement of an alternative probe apparatus; Figure 20 shows a method for non-destructive evaluation of an object under test,

[0334] Figure 21 shows an example of the method shown in Figure 20;

[0335] Figure 22 shows another example of the method shown in Figure 20;

[0336] Figure 23 shows another example of the method shown in Figure 20;

[0337] Figure 24 shows another method for non-destructive evaluation of an object under test,

[0338] Figure 25 shows an example of the method shown in Figure 24;

[0339] Figure 26 shows another example of the method shown in Figure 24;

[0340] Figure 27 shows another method for non-destructive evaluation of an object under test,

[0341] Figure 28 shows an example of the method shown in Figure 27;

[0342] Figure 29 shows another example of the method shown in Figure 27; and

[0343] Figures 30 to 40 of the accompanying drawings illustrate a probe apparatus for implementing the methods of Figures 27 to 29.

[0344] DETAILED DESCRIPTION OF DRAWINGS

[0345] Referring first to Figures 1 , 2 and 3 of the accompanying drawings, there is shown diagrammatic and cross-sectional views, respectively, of a probe apparatus, generally denoted 10, for use in the non-destructive evaluation of an object W under test.

[0346] As shown, the probe apparatus 10 comprises a transducer arrangement, generally denoted 12, which is configured and / or operable to direct an ultrasonic beam II towards the object under test W, a compliant element, generally denoted 14, which is configured to engage the object W, and an intermediate member, generally denoted 16, which is interposed between the transducer arrangement 12 and the compliant element 14.

[0347] As best shown in Figure 3, the intermediate member 16 and the compliant element 14 are arranged so as to define an interface 18 therebetween and, as will be described further below, the intermediate member 16 and the compliant element 14 are configured and / or operable to retain a fluid 20 disposed at the interface 18 between the intermediate member 16 and the compliant element 14. In use, the probe apparatus 10 is located on an object W under test, with the compliant element 14 subjected to a force urging the compliant element 14 into engagement or enhanced engagement with the object W under test. The transducer arrangement 12 is configured and / or operable to direct the ultrasonic beam II towards the object W, with one or more properties of a reflected beam R being detected by the transducer arrangement 12 and / or another detection arrangement to determine the properties, condition, integrity and / or behaviour of the object W under test. The probe apparatus 10 comprises an inlet arrangement, generally denoted 11 , which comprises one or more inlets 13. The probe apparatus 10 also comprises an outlet arrangement, generally denoted 15, which comprises one or more outlets 17. The intlet arrangement 11 and the outlet arrangement 15 are coupled to and / or operatively associated with a fluid arrangement, generally denoted 19. The fluid arrangement 19 comprises a cooling arrangement 21. The probe apparatus 10 comprises a valve arrangement, generally denoted 23. As discussed above, the fluid 20 is supplied to an internal volume 30 of the compliant element 14 by the fluid arrangement 19 via the inlet arrangement 11 , and is disposed within the probe apparatus 10, including at the interface 18 between the intermediate member 16 and the compliant element 14, the fluid 20 acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element 14 and onwards into the object W under test. The fluid 20 is cooled via the cooling arrangement 21 prior to being supplied to the internal volume 30. The fluid 20, having undergone an increase in temperature through use of the probe apparatus 10, is then removed by the fluid arrangement 19 from the internal volume 30 of the compliant element 14 via the outlet arrangement 15. Whilst removing the high temperature fluid 20 from the internal volume 30, the fluid arrangement 19 simultaneously supplies fluid 20 which has been cooled via the cooling arrangement 21 to the internal volume 30, in order to replace the high temperature fluid 20 removed. The cooling arrangement 21 then cools the high temperature fluid 20 removed, which is then resupplied to the internal volume 30 of the compliant element 14 via the inlet arrangement 11. In the present probe apparatus 10, one or both of the intermediate member 16 and the compliant element 14 are configured and / or operable to retain the fluid 20 disposed at the interface 18 between the intermediate member 16 and the compliant element 14.

[0348] The probe apparatus 10 provides a number of benefits over conventional equipment. For example, the probe apparatus 10 obviates or at least mitigates the likelihood that the fluid 20 will be evacuated from the interface 18 between the intermediate member 16 and the compliant element 14 when the probe apparatus 10 is in use, in particular but not exclusively due to the load force urging the intermediate member 16 into engagement with the compliant element 14 forcing the fluid 20 from the interface 18. This has the benefit of maintaining the cooling effect at the interface 18, which in turn facilitates use of the probe apparatus 10 at higher temperatures and / or prolonged effective use of the probe apparatus 10 at a given temperature.

[0349] Moreover, by obviating or at least mitigating the likelihood that the fluid 20 will be evacuated from the interface 18 between the intermediate member 12 and the compliant element 14, the effective transmission of the ultrasound beam II from the transducer arrangement 12 into the compliant element 14 and onwards into the object W under test is maintained. This in turn permits the apparatus 10 to be subjected to a greater range and / or variation in load force. For example, the apparatus 10 may be subjected to a greater load force so as to better conform with the object W under test, without detrimentally affecting the ability to communicate the ultrasonic beam II between the intermediate member 12 and the compliant element 14 and onwards into the object W. Alternatively, the apparatus 10 may be subjected to a reduced load force having obviated or at least mitigated the likelihood that the fluid 20 will be evacuated from the interface 18, the retention of the fluid 20 within the interface 18 ensuring the effective transmission of the ultrasound beam II when compared with conventional apparatuses without the reliance of said conventional apparatuses on the exertion of high load forces on the apparatus 10.

[0350] The probe apparatus 10 is configured and / or operable to facilitate dry-coupled inspection of the object W under test, i.e. without a liquid couplant between the probe apparatus 10 and the object W under test.

[0351] Beneficially, dry-coupled inspection facilitates faster evaluation of the object W under test and / or obviates the risk of the liquid couplant contaminating the object W under test and / or the environment. However, it will be understood that in some embodiments the probe apparatus 10 employs a liquid couplant, e.g. a gel.

[0352] The probe apparatus 10 finds particular application in the areas of weld inspection, for example but not exclusively facilitating high temperature compliant weld inspection to be carried out - both after the welding process and / or on in-service welds but also during and / or immediately after the welding process and so permits the welding process to be better controlled to ensure weld quality. This in turn beneficially obviates or at least mitigates the need for re-working and consequential benefits in terms of greater certainty of schedule and / or reduced manufacturing lead times.

[0353] Alternatively, the probe apparatus 10 finds particular application in the inspection of objects constructed using additive manufacturing techniques.

[0354] As described above, the probe apparatus 10 comprises a transducer arrangement 12 configured and / or operable to direct an ultrasonic beam II towards the object W under test.

[0355] In the illustrated embodiment, the transducer arrangement 12 comprises or take the form of a transducer array 22, the transducer arrangement 12 comprising or taking the form of a phased array ultrasonic transducer (PALIT) arrangement in particular

[0356] The transducer arrangement 12 is configured and / or operable to transmit and / or receive the ultrasonic beam II.

[0357] The transducer arrangement 12 is coupled to and / or operatively associated with an ultrasonic driver device 44.

[0358] In use, in order to create a constructive interference in the wavefronts in question, the ultrasonic beam II is focussed using time delays. Such interference allows the energy to be focused at any depth and angle within the object W. In order to be able to facilitate the creation of such constructive interference, the transducer arrangement 12 comprises transducers which transmit / receive independently at different times. Alternatively or additionally, as described above, the ultrasonic driver device 44 transmits the high voltage electric pulse, causing each of the one or more transmitters to transmit an ultrasonic beam II at an interval separate from each of the other transmitters, with the reflections from each of the ultrasonic beams II transmitted being received by the one or more receivers. The plurality of receivers having received the reflected ultrasonic beams II, the ultrasonic driver device 44 shall receive corresponding signals, which the ultrasonic driver device 44 shall record. Said recorded data may then be utilised in order to conduct advanced reconstruction in order to create a constructive interference in the wavefronts in question.

[0359] As described above, the probe apparatus 10 comprises the intermediate member 16 interposed between the transducer arrangement 12 and the compliant element 14.

[0360] In the illustrated embodiment, the intermediate member 16 comprises or takes the form of a wedge 24.

[0361] The intermediate member 16 is partially or wholly constructed from a plastic material, the plastic material comprising or taking the form of a thermoplastic material. In the illustrated embodiment, the plastic material comprises or takes the form of polyetherimide, e.g. Ultern®. Alternatively or additionally, the plastic material may comprise or take the form of polyimide, e.g. Vespel®. The plastic material may comprise or take the form of a polyamide-imide, e.g. Duratron®.

[0362] Beneficially, the intermediate member 16 provides high strength and high temperature capabilities, facilitating use in high temperature in-process non-destructive evaluation of objects, such as welds during and / or immediately after the welding process, metal objects during and / or immediately after the metal additive manufacturing process or composite components during and / or immediately after the manufacturing process.

[0363] As shown in Figure 4, the transducer arrangement 12 and the intermediate member 16 together form a transducer assembly, generally denoted 26, of the probe apparatus 10. At least one of the transducer assembly 26 and the compliant element 14 are configured and / or operable to retain a fluid 20 disposed at the interface 18 between the intermediate member 16 and the compliant element 14.

[0364] As described above, the probe apparatus 10 comprises the compliant element 14 configured for location between the intermediate member 16 and the object W under test.

[0365] The compliant element 14 is partially or wholly constructed from an elastomeric material, the elastomeric material comprising or taking the form of a silicone rubber material. In the illustrated embodiment, the compliant element 14 is partially or wholly constructed from high temperature silicone rubber.

[0366] Beneficially, the compliant element 14 is capable of conforming to the geometry of the object W under test and provides high strength and high temperature capabilities, facilitating use in high temperature in-process non-destructive evaluation of objects, such as welds during and / or immediately after the welding process, metal objects during and / or immediately after the metal additive manufacturing process or composite components during and / or immediately after the manufacturing process.

[0367] The compliant element 14 comprises or take the form of a cylindrical or substantially cylindrical element.

[0368] The probe apparatus 10 is configured so that the compliant element 14 moves relative to the intermediate member 16. For example, the probe apparatus 10 is configured so that the compliant element 14 rotates around the intermediate member 16 and / or the transducer arrangement 12. In the illustrated embodiment, the compliant element 14 comprises or takes the form of a rolling element 28, the compliant element 14 comprising or taking the form of a tyre, wheel or the like.

[0369] The probe apparatus 10 is configured so that the compliant element 14 moves axially relative to the intermediate member 16. As discussed above, the compliant element 14 at least partially defines an internal volume 30. The internal volume 30 comprises or takes the form of a chamber, the transducer assembly 26 being disposed within the internal volume 30.

[0370] The probe apparatus 10 comprises a support arrangement, generally denoted 32. The support arrangement 32 comprises or take the form of a mandrel 34. In use, the mandrel 34 forms an axle of the probe apparatus 10.

[0371] The transducer assembly 26 is supported, e.g. mounted, on the mandrel 34, the transducer assembly being fixedly coupled to, e.g. fixedly mounted on, the mandrel 34.

[0372] The compliant element 14 is movably supported, e.g. mounted on or coupled to, the mandrel 34. In the illustrated embodiment, the compliant element 14 is rotatably supported, e.g. rotatably mounted on or coupled to, the mandrel 34. The probe apparatus 10 comprises a bearing arrangement, generally denoted 36, for rotatably supporting the compliant element 14.

[0373] As described above, the intermediate member 16 and the compliant element 14 are arranged so as to define the interface 18 therebetween, and at least one of the intermediate member 16 and the compliant element 14 are configured and / or operable to retain the fluid 20 disposed at the interface 18 between the intermediate member 16 and the compliant element 14.

[0374] The configuration of the intermediate member 16 and / or the compliant element 14 so as to retain the fluid 20 disposed at the interface 18 may take a number of different forms.

[0375] For example, the configuration of the intermediate member 16 and / or the compliant element 14 so as to retain the fluid disposed at the interface comprises or takes the form of a surface treatment.

[0376] Figures 5A to 5D of the accompanying drawings show possible configurations 38a, 38b, 38c, 38d of the intermediate member 16 and / or the compliant element 14 following surface treatment. The one or more of the surface treatment processes are applied to the intermediate member 16 and / or to the mould used to form the intermediate member 16.

[0377] The surface roughness of the intermediate member 16 is selected based on the frequency and / or wavelength of the ultrasonic beam II.

[0378] For example, the surface roughness may be selected to be:

[0379] Ra < A / 10,

[0380] Where Ra is surface roughness

[0381] Where A is wavelength.

[0382] Beneficially, this minimises or at least reduces wavefront aberration.

[0383] In the illustrated embodiment, the surface treatment is also formed or otherwise provided on a surface 40 of the compliant element 14 which faces the intermediate member 16, which in the illustrated embodiment is the internal surface of the compliant element 14.

[0384] The one or more of processes are applied to the compliant element 14 and / or to the mould used to form the compliant element 14.

[0385] The surface roughness of the compliant element 14 is selected based on the frequency and / or wavelength of the ultrasonic beam II.

[0386] For example, the surface roughness may be selected to be:

[0387] Ra < A / 10,

[0388] Where Ra is surface roughness Where A is wavelength.

[0389] Beneficially, this minimises or at least reduces wavefront aberration. As described above, in use, the probe apparatus 10 is located on an object W under test, with the compliant element 14 subjected to a force urging the compliant element 14 into engagement or enhanced engagement with the object W under test. The transducer arrangement 12 is configured and / or operable to direct an ultrasonic beam II towards the object W, with one or more properties of a reflected beam R being detected by the transducer arrangement 12 and / or another detection arrangement to determine the properties, condition, integrity and / or behaviour of the object W under test. As discussed above, the fluid 20 is disposed within the probe apparatus 10, including at the interface 18 between the intermediate member 16 and the compliant element 14, the fluid 20 acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element 14 and onwards into the object W under test. In the present probe apparatus 10, one or both of the intermediate member 16 and the compliant element 14 are configured and / or operable to retain the fluid 20 disposed at the interface 18 between the intermediate member 16 and the compliant element 14.

[0390] In the illustrated embodiment, the intermediate member 16 and the compliant element 14 are reconfigurable from a first configuration in which the intermediate member 16 and the compliant element 14 are spaced from each other to a second configuration, e.g. in response to the applied load, in which the intermediate member 16 engages the compliant element 14 and which prevents the fluid 20 in the interface 18 from escaping.

[0391] The probe apparatus 10 comprises an absorber 42, the absorber 42 being configured and / or operable to absorb ultrasonic waves.

[0392] Beneficially, the absorber 42 prevents undesired reflected waves / signals affecting the evaluation.

[0393] As described above, the fluid 20 is disposed within the probe apparatus 10, including at the interface 18 between the intermediate member 16 and the compliant element 14, the fluid 20 acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound II into the compliant element 14 and onwards into the object W under test. In the present probe apparatus 10, one or both of the intermediate member 16 and the compliant element 14 are configured and / or operable to retain the fluid 20 disposed at the interface 18 between the intermediate member 16 and the compliant element 14.

[0394] The fluid 20 is configured and / or operable to act as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound II into the compliant element 14 and onwards into the object W under test.

[0395] In the illustrated embodiment, the fluid 20 comprises or takes the form of a liquid.

[0396] As shown in Figure 6 of the accompanying drawings, there is provided a system, generally denoted 1000, for use in non-destructive evaluation of the object W under test, comprising the probe apparatus 10 of Figure 1.

[0397] Referring now to Figures 7 to 10 of the accompanying drawings, there are shown perspective views of a probe apparatus, generally denoted 110, for use in the nondestructive evaluation of an object W under test.

[0398] As shown, the probe apparatus 110 comprises a transducer arrangement, generally denoted 112, configured and / or operable to direct an ultrasonic beam II towards the object W under test, a compliant element, generally denoted 114, being configured to engage the object W under test, and an intermediate member, generally denoted 116, being interposed between the transducer arrangement 112 and the compliant element 114.

[0399] In the illustrated apparatus 110, the probe apparatus 110 is configured and / or operable to control an angle of inclination of the compliant element 114 so as to reduce a deviation in the ultrasonic beam II propagating in the object W under test.

[0400] In use, the probe apparatus 110 is located on an object W under test, with the compliant element 114 being subjected to a force urging the compliant element 114 into engagement or enhanced engagement with the object W under test. The transducer arrangement 112 is configured and / or operable to direct the ultrasonic beam II towards the object W, with one or more properties of a reflected beam R being detected by the transducer arrangement 112 and / or another detection arrangement to determine the properties, condition, integrity and / or behaviour of the object W under test. The probe apparatus 110 comprises an inlet arrangement, generally denoted 111 , which comprises one or more inlets 113. The probe apparatus 110 also comprises an outlet arrangement, generally denoted 115, which comprises one or more outlets 117. The intlet arrangement 111 and the outlet arrangement 115 are coupled to and / or operatively associated with a fluid arrangement, generally denoted 119. The fluid arrangement 119 comprises a cooling arrangement 121. The probe apparatus 10 comprises a valve arrangement, generally denoted 123. As will be described further below, a fluid 120 is supplied to an internal volume 130 of the compliant element 114 by the fluid arrangement 119 via the inlet arrangement 111 , and is disposed within the probe apparatus 110, including at an interface 118 between an intermediate member 116 and the compliant element 114, the fluid 120 acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element 114 and onwards into the object W under test. The fluid 120 is cooled via the cooling arrangement 121 prior to being supplied to the internal volume 130. The fluid 120, having undergone an increase in temperature through use of the probe apparatus 110, is then removed by the fluid arrangement 119 from the internal volume 130 of the compliant element 114 via the outlet arrangement 115. Whilst removing the high temperature fluid 120 from the internal volume 130, the fluid arrangement 119 simultaneously supplies fluid 120 which has been cooled via the cooling arrangement 121 to the internal volume 130, in order to replace the high temperature fluid 120 removed. The cooling arrangement 121 then cools the high temperature fluid 120 removed, which is then resupplied to the internal volume 130 of the compliant element 114 via the inlet arrangement 111. In the present probe apparatus 110, the probe apparatus 110 is configured and / or operable to control an angle of inclination of the compliant element 114 so as to reduce a deviation in the ultrasonic beam II propagating in the object W under test.

[0401] It has been found that a 1 degree difference in inclination of the inner and outer surfaces of the compliant element 114 results in a much larger deviation in the ultrasonic beam II path inside the object W under test. For example, the compliant element 114 often comprises a material through which sound travels at a reduced speed when compared to those materials which the intermediate member 116 and the object W under test respectively comprise. Thus, as an ultrasonic beam II travels from the intermediate member 116 to the compliant element 114, the beam II is refracted, resulting in a significant change in the angle of the ultrasonic beam II. A similar process of refraction occurs as the beam II travels from the compliant element 114 to the object W under test. Where the inner and outer surfaces of the compliant element 114 are maintained parallel relative to one another, the angle of the ultrasonic beam II path inside the object W under test remains unaffected. Beneficially, the probe apparatus 110 compensates for a deviation in the ultrasonic beam II propagating in the object W under test resulting from the ultrasonic beam II propagating through a compliant element 114 having inner and outer surfaces which are non-parallel.

[0402] The probe apparatus 110 comprises a passive arrangement, generally denoted 146, for controlling the inclination of the compliant element 114.

[0403] In the illustrated apparatus 110, the passive arrangement 146 comprises a plurality of wheels 150, the wheels 150 of the passive arrangement 146 configured and / or operable to control the alignment of the compliant element 114.

[0404] As discussed above, the intermediate member 116 and the compliant element 114 are arranged so as to define the interface 118 therebetween. At least one of the intermediate member 116 and the compliant element 114 are configured and / or operable to retain the fluid 120 disposed at the interface 118 between the the intermediate member 116 and the compliant element 114.

[0405] In use, the probe apparatus 110 is located on the object W under test, with the compliant element 114 subjected to a force urging the compliant element 114 into engagement or enhanced engagement with the object W under test. The transducer arrangement 112 is configured and / or operable to direct an ultrasonic beam II towards the object W, with one or more properties of a reflected beam R being detected by the transducer arrangement 112 and / or another detection arrangement to determine the properties, condition, integrity and / or behaviour of the object W under test. As discussed above, the fluid 120 is disposed within the probe apparatus 110, including at the interface 118 between the intermediate member 116 and the compliant element 114, the fluid 120 acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element 114 and onwards into the object W under test. In the present probe apparatus 110, one or both of the intermediate member 116 and the compliant element 114 are configured and / or operable to retain the fluid 120 disposed at the interface 118 between the intermediate member 116 and the compliant element 114. As described above, the probe apparatus 110 comprises a transducer arrangement 112 configured and / or operable to direct an ultrasonic beam II towards the object W under test.

[0406] In the illustrated apparatus 110, the transducer arrangement 112 comprises or take the form of a transducer array 122, the transducer arrangement 112 comprising or taking the form of a phased array ultrasonic transducer (PALIT) arrangement in particular

[0407] The transducer arrangement 112 is configured and / or operable to transmit and / or receive the ultrasonic beam II.

[0408] The transducer arrangement 112 is coupled to and / or operatively associated with an ultrasonic driver device 144.

[0409] In use, in order to create a constructive interference in the wavefronts in question, the ultrasonic beam II is focussed using time delays. Such interference allows the energy to be focused at any depth and angle within the object W. In order to be able to facilitate the creation of such constructive interference, the transducer arrangement 112 comprises transducers which transmit / receive independently at different times.

[0410] Alternatively or additionally, as described above, the ultrasonic driver device 144 transmits the high voltage electric pulse, causing each of the one or more transmitters to transmit an ultrasonic beam II at an interval separate from each of the other transmitters, with the reflections from each of the ultrasonic beams II transmitted being received by the one or more receivers. The plurality of receivers having received the reflected ultrasonic beams II, the ultrasonic driver device 144 shall receive corresponding signals, which the ultrasonic driver device 144 shall record. Said recorded data may then be utilised in order to conduct advanced reconstruction in order to create a constructive interference in the wavefronts in question.

[0411] As described above, the probe apparatus 110 comprises the intermediate member 116 interposed between the transducer arrangement 112 and the compliant element 114. In the illustrated apparatus 110, the intermediate member 116 comprises or takes the form of a wedge 124.

[0412] The intermediate member 116 is partially or wholly constructed from a plastic material, the plastic material comprising or taking the form of a thermoplastic material. In the illustrated embodiment, the plastic material comprises or takes the form of polyetherimide, e.g. Ultern®. Alternatively or additionally, the plastic material may comprise or take the form of polyimide, e.g. Vespel®. The plastic material may comprise or take the form of a polyamide-imide, e.g. Duratron®.

[0413] Beneficially, the intermediate member 116 provides high strength and high temperature capabilities, facilitating use in high temperature in-process non-destructive evaluation of objects, such as welds during and / or immediately after the welding process, metal objects during and / or immediately after the metal additive manufacturing process or composite components during and / or immediately after the manufacturing process.

[0414] As shown in Figure 11 , the transducer arrangement 112 and the intermediate member 116 together form a transducer assembly 126 of the probe apparatus 110.

[0415] At least one of the transducer assembly 126 and the compliant element 114 are configured and / or operable to retain a fluid 120 disposed at the interface 118 between the intermediate member 116and the compliant element 114.

[0416] As described above, the probe apparatus 110 comprises the compliant element 114 configured for location between the intermediate member 116 and the object W under test.

[0417] The compliant element 114 is partially or wholly constructed from an elastomeric material, the elastomeric material comprising or taking the form of a silicone rubber material. In the illustrated embodiment, the compliant element 114 is partially or wholly constructed from high temperature silicone rubber.

[0418] Beneficially, the compliant element 114 is capable of conforming to the geometry of the object W under test and provides high strength and high temperature capabilities, facilitating use in high temperature in-process non-destructive evaluation of objects, such as welds during and / or immediately after the welding process, metal objects during and / or immediately after the metal additive manufacturing process or composite components during and / or immediately after the manufacturing process.

[0419] The compliant element 114 comprises or take the form of a cylindrical or substantially cylindrical element.

[0420] The probe apparatus 110 is configured so that the compliant element 114 moves relative to the intermediate member 116. For example, the probe apparatus 110 is configured so that the compliant element 114 rotates around the intermediate member 16 and / or the transducer arrangement 112. In the illustrated embodiment, the compliant element 114 comprises or takes the form of a rolling element 128, the compliant element 114 comprising or taking the form of a tyre, wheel or the like.

[0421] The probe apparatus 110 is configured so that the compliant element 114 moves axially relative to the intermediate member 116.

[0422] The compliant element 114 at least partially defines an internal volume 130. The internal volume 130 comprises or takes the form of a chamber, the transducer assembly 126 being disposed within the internal volume 130.

[0423] The probe apparatus 110 comprises a support arrangement, generally denoted 132. The support arrangement 132 comprises or take the form of a mandrel 134. In use, the mandrel 134 forms an axle of the probe apparatus 110.

[0424] The transducer assembly 126 is supported, e.g. mounted, on the mandrel 134, the transducer assembly being fixedly coupled to, e.g. fixedly mounted on, the mandrel 134.

[0425] The compliant element 114 is movably supported, e.g. mounted on or coupled to, the mandrel 134. In the illustrated embodiment, the compliant element 114 is rotatably supported, e.g. rotatably mounted on or coupled to, the mandrel 134. The probe apparatus 110 comprises a bearing arrangement 136 for rotatably supporting the compliant element 114. As described above, the intermediate member 116 and the compliant element 114 are arranged so as to define the interface 116 therebetween, and at least one of the intermediate member 116 and the compliant element 114 are configured and / or operable to retain the fluid 120 disposed at the interface 118 between the intermediate member 116 and the compliant element 114.

[0426] The configuration of the intermediate member 116 and / or the compliant element 114 so as to retain the fluid 120 disposed at the interface 118 may take a number of different forms.

[0427] For example, the configuration of the intermediate member 116 and / or the compliant element 114 so as to retain the fluid disposed at the interface comprises or takes the form of a surface treatment.

[0428] Figures 12A to 12D of the accompanying drawings show possible configurations 138a, 138b, 138c, 138d of the intermediate member 116 and / or the compliant element 114 following surface treatment.

[0429] The one or more of the surface treatment processes are applied to the intermediate member 116 and / or to the mould used to form the intermediate member 116.

[0430] The surface roughness of the intermediate member 116 is selected based on the frequency and / or wavelength of the ultrasonic beam II.

[0431] For example, the surface roughness may be selected to be:

[0432] Ra < A / 10,

[0433] Where Ra is surface roughness Where A is wavelength.

[0434] Beneficially, this minimises or at least reduces wavefront aberration. In the illustrated apparatus 110, the surface treatment is also formed or otherwise provided on a surface 140 of the compliant element 114 which faces the intermediate member 116, which in the illustrated embodiment is the internal surface of the compliant element 114.

[0435] The one or more of processes are applied to the compliant element 114 and / or to the mould used to form the compliant element 114.

[0436] The surface roughness of the compliant element 114 is selected based on the frequency and / or wavelength of the ultrasonic beam II.

[0437] For example, the surface roughness may be selected to be:

[0438] Ra < A / 10,

[0439] Where Ra is surface roughness

[0440] Where A is wavelength.

[0441] Beneficially, this minimises or at least reduces wavefront aberration.

[0442] As described above, in use, the probe apparatus 110 is located on an object W under test, with the compliant element 114 subjected to a force urging the compliant element 114 into engagement or enhanced engagement with the object W under test. The transducer arrangement 112 is configured and / or operable to direct an ultrasonic beam II towards the object W, with one or more properties of a reflected beam R being detected by the transducer arrangement 112 and / or another detection arrangement to determine the properties, condition, integrity and / or behaviour of the object W under test. The probe apparatus 110 comprises an inlet arrangement, generally denoted 111 , which comprises one or more inlets 113. The probe apparatus 110 also comprises an outlet arrangement, generally denoted 115, which comprises one or more outlets 117. The intlet arrangement 111 and the outlet arrangement 115 are coupled to and / or operatively associated with a fluid arrangement, generally denoted 119. The fluid arrangement 119 comprises a cooling arrangement 121. The probe apparatus 10 comprises a valve arrangement, generally denoted 123. As discussed above, the fluid 120 is supplied to an internal volume 130 of the compliant element 114 by the fluid arrangement 119 via the inlet arrangement 111 , and is disposed within the probe apparatus 110, including at the interface 118 between the intermediate member 116 and the compliant element 114, the fluid 120 acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound into the compliant element 114 and onwards into the object W under test. The fluid 120 is cooled via the cooling arrangement 121 prior to being supplied to the internal volume 130. The fluid 120, having undergone an increase in temperature through use of the probe apparatus 110, is then removed by the fluid arrangement 119 from the internal volume 130 of the compliant element 114 via the outlet arrangement 115. Whilst removing the high temperature fluid 120 from the internal volume 130, the fluid arrangement 119 simultaneously supplies fluid 120 which has been cooled via the cooling arrangement 121 to the internal volume 130, in order to replace the high temperature fluid 120 removed. The cooling arrangement 121 then cools the high temperature fluid 120 removed, which is then resupplied to the internal volume 130 of the compliant element 114 via the inlet arrangement 111. In the present probe apparatus 110, one or both of the intermediate member 116 and the compliant element 114 are configured and / or operable to retain the fluid 120 disposed at the interface 118 between the intermediate member 116and the compliant element 114.

[0443] In the illustrated apparatus 110, the intermediate member 116 and the compliant element 114 are reconfigurable from a first configuration in which the intermediate member 116 and the compliant element 114 are spaced from each other to a second configuration, e.g. in response to the applied load, in which the intermediate member 116 engages the compliant element 114 and which prevents the fluid 120 in the interface 118 from escaping.

[0444] The probe apparatus 110 comprises an absorber 142, the absorber 142 being configured and / or operable to absorb ultrasonic waves.

[0445] Beneficially, the absorber 142 prevents undesired reflected waves / signals affecting the evaluation.

[0446] As described above, the fluid 120 is disposed within the probe apparatus 110, including at the interface 118 between the intermediate member 116 and the compliant element 114, the fluid 120 acting as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound II into the compliant element 114 and onwards into the object W under test. In the present probe apparatus 110, one or both of the intermediate member 116 and the compliant element 114 are configured and / or operable to retain the fluid 120 disposed at the interface 118 between the intermediate member 116 and the compliant element 114.

[0447] The fluid 120 is configured and / or operable to act as a coolant and / or an internal coupling which facilitates the transmission of the ultrasound II into the compliant element 114 and onwards into the object W under test.

[0448] In the illustrated apparatus 110, the fluid 120 comprises or takes the form of a liquid.

[0449] As shown in Figure 13, there is provided a system 2000 for use in non-destructive evaluation of the object W under test, comprising the probe apparatus 110 of Figure 7.

[0450] As shown in Figure 14, there is provided a graph illustrating error propagation due to angle deviation.

[0451] As shown in Figure 15, there is provided a graph of parametric analysis of beam angle error for a variety of angles of the compliant element vs intended ultrasonic beam angle.

[0452] As shown in Figure 16, there is provided an alternative probe apparatus, generally denoted 210, for use in the non-destructive evaluation of an object W under test.

[0453] It has been found that a 1 degree difference in inclination of the inner and outer surfaces of the compliant element 214 results in a much larger deviation in the ultrasonic beam II path inside the object W under test. For example, the compliant element 214 often comprises a material through which sound travels at a reduced speed when compared to those materials which the intermediate member 216 and the object W under test respectively comprise. Thus, as an ultrasonic beam II travels from the intermediate member 216 to the compliant element 214, the beam II is refracted, resulting in a significant change in the angle of the ultrasonic beam II. A similar process of refraction occurs as the beam II travels from the compliant element 214 to the object W under test. Where the inner and outer surfaces of the compliant element 214 are maintained parallel relative to one another, the angle of the ultrasonic beam II path inside the object W under test remains unaffected. Beneficially, the probe apparatus 210 compensates for a deviation in the ultrasonic beam II propagating in the object W under test resulting from the ultrasonic beam II propagating through a compliant element 214 having inner and outer surfaces which are non-parallel.

[0454] The probe apparatus 210 is coupled to and / or operatively associated with an active arrangement, generally denoted 252, for controlling the inclination of the compliant element 214, the active arrangement 252 comprising a robotic arm 254.

[0455] The active arrangement 252 comprises a sensor arrangement, generally denoted 256, the sensor arrangement 256 configured and / or operable to measure the angle of the object under test W and / or the angle between the sensor arrangement 256 and the object under test W, and adapt the inclination of the compliant element 214 accordingly, in real-time. The sensor arrangement 256 comprises one or more sensors. For example, the sensor arrangement 256 comprises one or more contactless distance measurement sensors, such as laser profilers, IR distance sensors and or ultrasonic distance sensors. The sensor arrangement, for example, also comprises one or more force and / or torque sensors.

[0456] As shown in Figure 17, there is provided a diagrammatic view of the transducer arrangement 312 and intermediate member 316 of an alternative probe apparatus 310. It shall be understood that apparatus 310 is similar to apparatus 10, and that like components are referenced using like reference numerals incremented by 300.

[0457] As shown in Figure 18, there is provided a cross-sectional view of the transducer arrangement 412 and the plurality of intermediate members 416 of an alternative probe apparatus 410. As shown, the transducer assembly 426 is arranged so as to form a transmit receive longitudinal (TRL) arrangement. Each of the plurality of intermediate members 416 are angled such that the ultrasonic beams II transmitted by the plurality of transducers 422 of the transducer arrangement 412 converge at a focal point. It shall be understood that apparatus 410 is similar to apparatus 10, and that like components are referenced using like reference numerals, incremented by 400. As shown in Figure 19, there is provided a perspective view of the transducer arrangement 512 of an alternative probe apparatus 510. As shown, the transducer arrangement 512 comprises or takes the form of a matrix array. It shall be understood that apparatus 510 is similar to apparatus 10, and that like components are referenced using like reference numerals, incremented by 500.

[0458] Figure 20 shows a method for non-destructive evaluation of an object under test, the object under test comprising or taking the form of a non-welded construction.

[0459] As shown in Figure 20, the method comprises the steps of: emitting ultrasound into the object under test; receiving ultrasound back from the object under test; acquiring multiple signal sets, including a first signal set and a second signal set; and processing the first signal set and the second signal set to provide evaluation data relating to the object under test.

[0460] The first signal set comprises a first series of first data elements, the first series of data elements spanning a first time period. Each first data element includes a first variable value for a variable and a first time value for that first variable value. The first time period includes a first time sub-period.

[0461] The second signal set comprises a second series of second data elements, the second series of second data elements spanning a second time period. Each second data element includes a second variable value for the variable and a second time value for that second variable value. The second time period includes a second time sub-period.

[0462] The first time sub-period and the second time sub-period cover the same time values.

[0463] The processing of the first signal set and the second signal set determines a modified signal set which contributes to the evaluation data. The modified signal set includes a modified time sub-period covering the same time values as the first time sub-period and the second time sub-period, and includes, for a time value, an expression of the first variable value for that time value and an expression of the second variable value for that time value, if the first variable value and the second variable value are within a given relationship to one another; and / or includes, for a time value, one of an expression of the first variable value for that time value or an expression of the second variable value for that time value, if the first variable value and the second variable value are not within a given relationship to one another.

[0464] Referring now also to Figures 21 , 22 and 23 of the accompanying drawings, there are shown examples of the method shown in Figure 20.

[0465] Figure 21 shows a method for non-destructive evaluation of an object under test, wherein the object under test comprises or takes the form of a non-welded construction in the form of an object constructed using additive manufacturing techniques.

[0466] In the illustrated method, the object under test comprises or takes the form of an object constructed using metal additive manufacturing, more specifically wire arc additive manufacturing (WAAM).

[0467] The method shown in Figure 21 may thus be defined as a method for use in the non-destructive evaluation of an object constructed using additive manufacturing techniques. The method may thus be further defined as a method for use in the nondestructive evaluation of an object constructed using metal additive manufacturing techniques, such as but not limited to wire arc additive manufacturing (WAAM).

[0468] As shown in Figure 21 , the method comprises emitting ultrasound into the object under test, receiving ultrasound back from the object under test, acquiring multiple signal sets, including a first signal set and a second signal set, and processing the first signal set and the second signal set to provide evaluation data relating to the object under test. In the illustrated method, the method further comprises the preliminary step of providing a probe apparatus and disposing the probe apparatus relative to the object under test so as to permit the probe apparatus to emit ultrasound into the object under test and receive ultrasound back from the object under test.

[0469] The method comprises locating the probe apparatus in proximity to the object under test.

[0470] In the illustrated method, the method comprises locating the probe apparatus in contact with the object under test.

[0471] However, it will be understood that in alternative methods, the probe apparatus may be located adjacent to the object under test without contacting the object under test.

[0472] As in the method shown and described in Figure 20, in the method of Figure 21 the first signal set comprises a first series of first data elements, the first series of data elements spanning a first time period. Each first data element includes a first variable value for a variable and a first time value for that first variable value. The first time period includes a first time sub-period.

[0473] The second signal set comprises a second series of second data elements, the second series of second data elements spanning a second time period. Each second data element includes a second variable value for the variable and a second time value for that second variable value. The second time period includes a second time sub-period.

[0474] The first time sub-period and the second time sub-period cover the same time values.

[0475] The processing of the first signal set and the second signal set determines a modified signal set which contributes to the evaluation data.

[0476] The modified signal set includes a modified time sub-period covering the same time values as the first time sub-period and the second time sub-period, and includes, for a time value, an expression of the first variable value for that time value and an expression of the second variable value for that time value, if the first variable value and the second variable value are within a given relationship to one another; and / or includes, for a time value, one of an expression of the first variable value for that time value or an expression of the second variable value for that time value, if the first variable value and the second variable value are not within a given relationship to one another.

[0477] Figure 22 shows another example of the method shown in Figure 20, wherein the object under test comprises or takes the form of a non-welded construction in the form of an object constructed from a composite material.

[0478] The method shown in Figure 22 may thus be defined as a method for use in the non-destructive evaluation of an object constructed from a composite material.

[0479] As shown in Figure 22, the method comprises emitting ultrasound into the object under test, receiving ultrasound back from the object under test, acquiring multiple signal sets, including a first signal set and a second signal set, and processing the first signal set and the second signal set to provide evaluation data relating to the object under test.

[0480] In the illustrated method, the method further comprises the preliminary step of providing a probe apparatus and disposing the probe apparatus relative to the object under test so as to permit the probe apparatus to emit ultrasound into the object under test and receive ultrasound back from the object under test.

[0481] The method comprises locating the probe apparatus in proximity to the object under test.

[0482] In the illustrated method, the method comprises locating the probe apparatus in contact with the object under test.

[0483] However, it will be understood that in alternative methods, the probe apparatus may be located adjacent to the object under test without contacting the object under test. As in the method shown and described in Figure 20, in the method of Figure 22 the first signal set comprises a first series of first data elements, the first series of data elements spanning a first time period. Each first data element includes a first variable value for a variable and a first time value for that first variable value. The first time period includes a first time sub-period.

[0484] The second signal set comprises a second series of second data elements, the second series of second data elements spanning a second time period. Each second data element includes a second variable value for the variable and a second time value for that second variable value. The second time period includes a second time sub-period.

[0485] The first time sub-period and the second time sub-period cover the same time values.

[0486] The processing of the first signal set and the second signal set determines a modified signal set which contributes to the evaluation data.

[0487] The modified signal set includes a modified time sub-period covering the same time values as the first time sub-period and the second time sub-period, and includes, for a time value, an expression of the first variable value for that time value and an expression of the second variable value for that time value, if the first variable value and the second variable value are within a given relationship to one another; and / or includes, for a time value, one of an expression of the first variable value for that time value or an expression of the second variable value for that time value, if the first variable value and the second variable value are not within a given relationship to one another.

[0488] Figure 23 shows another example of the method shown in Figure 20, wherein the object under test comprises or takes the form of a non-welded construction in the form of an object constructed from a human or animal body.

[0489] The method shown in Figure 23 may thus be defined as a method for non-evasive evaluation of a human or animal body. In the illustrated method, the method further comprises the preliminary step of providing a probe apparatus and disposing the probe apparatus relative to the object under test so as to permit the probe apparatus to emit ultrasound into the object under test and receive ultrasound back from the object under test.

[0490] The method comprises locating the probe apparatus in proximity to the object under test.

[0491] In the illustrated method, the method comprises locating the probe apparatus in contact with the object under test.

[0492] However, it will be understood that in alternative methods, the probe apparatus may be located adjacent to the object under test without contacting the object under test.

[0493] As in the method shown and described in Figure 20, in the method of Figure 23 the first signal set comprises a first series of first data elements, the first series of data elements spanning a first time period. Each first data element includes a first variable value for a variable and a first time value for that first variable value. The first time period includes a first time sub-period.

[0494] The second signal set comprises a second series of second data elements, the second series of second data elements spanning a second time period. Each second data element includes a second variable value for the variable and a second time value for that second variable value. The second time period includes a second time sub-period.

[0495] The first time sub-period and the second time sub-period cover the same time values.

[0496] The processing of the first signal set and the second signal set determines a modified signal set which contributes to the evaluation data. The modified signal set includes a modified time sub-period covering the same time values as the first time sub-period and the second time sub-period, and includes, for a time value, an expression of the first variable value for that time value and an expression of the second variable value for that time value, if the first variable value and the second variable value are within a given relationship to one another; and / or includes, for a time value, one of an expression of the first variable value for that time value or an expression of the second variable value for that time value, if the first variable value and the second variable value are not within a given relationship to one another.

[0497] Figure 24 shows another method for non-destructive evaluation of an object under test, the object under test comprising or taking the form of a non-welded construction.

[0498] As shown in Figure 24, the method comprises the steps of: emitting an ultrasound wave into a volume of a non-welded construction provided at an elevated temperature state above ambient temperature; receiving at least part of the ultrasound wave back from the nonwelded construction; acquiring multiple signal sets; processing one or more of the multiple signal sets to provide evaluation data relating to the non-welded construction, wherein the processing includes a correction for temperature within the volume of the object under test at the elevated temperature.

[0499] Referring now also to Figures 25 and 26 of the accompanying drawings, there are shown examples of the method shown in Figure 24.

[0500] Figure 25 shows a method for non-destructive evaluation of an object under test, wherein the object under test comprises or takes the form of a non-welded construction in the form of an object constructed using additive manufacturing techniques. In the illustrated method, the object under test comprises or takes the form of an object constructed using metal additive manufacturing, more specifically wire arc additive manufacturing (WAAM).

[0501] The method shown in Figure 25 may thus be defined as a method for use in the non-destructive evaluation of an object constructed using additive manufacturing techniques. The method may thus be further defined as a method for use in the nondestructive evaluation of an object constructed using metal additive manufacturing techniques, such as but not limited to wire arc additive manufacturing (WAAM).

[0502] As shown in Figure 25, the method comprises the steps of: emitting an ultrasound wave into a volume of a non-welded construction provided at an elevated temperature state above ambient temperature; receiving at least part of the ultrasound wave back from the nonwelded construction; acquiring multiple signal sets; processing one or more of the multiple signal sets to provide evaluation data relating to the non-welded construction, wherein the processing includes a correction for temperature within the volume of the object under test at the elevated temperature.

[0503] In the illustrated method, the method further comprises the preliminary step of providing the object under test at an elevated temperature state above ambient temperature by heating during the evaluation.

[0504] The method comprises locating the probe apparatus in proximity to the object under test.

[0505] In the illustrated method, the method comprises locating the probe apparatus in contact with the object under test.

[0506] However, it will be understood that in alternative methods, the probe apparatus may be located adjacent to the object under test without contacting the object under test. As in the method shown and described in Figure 24, in the method of Figure 25, the object under test is provided at an elevated temperature state above ambient temperature by heating during the evaluation, and the processing includes a correction for temperature within the volume of the object under test at the elevated temperature.

[0507] Figure 26 shows another example of the method shown in Figure 24, wherein the object under test comprises or takes the form of a non-welded construction in the form of an object constructed from a composite material.

[0508] The method shown in Figure 26 may thus be defined as a method for use in the non-destructive evaluation of an object constructed from a composite material.

[0509] As shown in Figure 26, the method comprises the steps of: emitting an ultrasound wave into a volume of a non-welded construction provided at an elevated temperature state above ambient temperature; receiving at least part of the ultrasound wave back from the nonwelded construction; acquiring multiple signal sets; processing one or more of the multiple signal sets to provide evaluation data relating to the non-welded construction, wherein the processing includes a correction for temperature within the volume of the object under test at the elevated temperature.

[0510] In the illustrated method, the method further comprises the preliminary step of providing the object under test at an elevated temperature state above ambient temperature by heating during the evaluation.

[0511] The method comprises locating the probe apparatus in proximity to the object under test.

[0512] In the illustrated method, the method comprises locating the probe apparatus in contact with the object under test. However, it will be understood that in alternative methods, the probe apparatus may be located adjacent to the object under test without contacting the object under test.

[0513] As in the method shown and described in Figure 24, in the method of Figure 26, the object under test is provided at an elevated temperature state above ambient temperature by heating during the evaluation, and the processing includes a correction for temperature within the volume of the object under test at the elevated temperature.

[0514] Figure 27 shows another method for non-destructive evaluation of an object under test, the object under test comprising or taking the form of a nonwelded construction.

[0515] As shown in Figure 27, the method comprises: passing ultrasound from a transducer of the ultrasound probe into the non-welded construction; detecting ultrasound returns from the non-welded construction; feeding coolant into an internal volume of the probe via a coolant inlet of the probe during the passing of ultrasound; and removing coolant from the internal volume of the probe via a coolant outlet of the probe during the passing of ultrasound.

[0516] The ultrasound probe comprises an axial element. The ultrasound emitting transducer is mounted on the axial element. Two or more support elements are rotatable mounted relative to the axial element. The compliant element is mounted on the two or more support elements and provides a continuous surface in at least one direction. The two or more support elements and the compliant element at least partially define the internal volume of the probe, the transducer being provided within the internal volume.

[0517] Referring now also to Figures 28 and 29 of the accompanying drawings, there are shown examples of the method shown in Figure 27. Figure 28 shows a method for non-destructive evaluation of an object under test, wherein the object under test comprises or takes the form of a non-welded construction in the form of an object constructed using additive manufacturing techniques.

[0518] In the illustrated method, the object under test comprises or takes the form of an object constructed using metal additive manufacturing, more specifically wire arc additive manufacturing (WAAM).

[0519] The method shown in Figure 28 may thus be defined as a method for use in the non-destructive evaluation of an object constructed using additive manufacturing techniques. The method may thus be further defined as a method for use in the nondestructive evaluation of an object constructed using metal additive manufacturing techniques, such as but not limited to wire arc additive manufacturing (WAAM).

[0520] As shown in Figure 28, the method comprises: passing ultrasound from a transducer of the ultrasound probe into the non-welded construction; detecting ultrasound returns from the non-welded construction; feeding coolant into an internal volume of the probe via a coolant inlet of the probe during the passing of ultrasound; and removing coolant from the internal volume of the probe via a coolant outlet of the probe during the passing of ultrasound.

[0521] The method may comprise the preliminary step of providing the ultrasound probe and placing at least a section of a compliant element of an ultrasound probe in contact with an object constructed using metal additive manufacturing.

[0522] The method comprises locating the probe apparatus in proximity to the object under test.

[0523] In the illustrated method, the method comprises locating the probe apparatus in contact with the object under test. However, it will be understood that in alternative methods, the probe apparatus may be located adjacent to the object under test without contacting the object under test.

[0524] As in the method shown and described in Figure 27, in the method of Figure 28 the ultrasound probe comprises an axial element. The ultrasound emitting transducer is mounted on the axial element. Two or more support elements are rotatable mounted relative to the axial element. The compliant element is mounted on the two or more support elements and provides a continuous surface in at least one direction. The two or more support elements and the compliant element at least partially define the internal volume of the probe, the transducer being provided within the internal volume.

[0525] Figure 29 shows another example of the method shown in Figure 27, wherein the object under test comprises or takes the form of a non-welded construction in the form of an object constructed from a composite material.

[0526] The method shown in Figure 29 may thus be defined as a method for use in the non-destructive evaluation of an object constructed from a composite material.

[0527] As shown in Figure 29, the method comprises: passing ultrasound from a transducer of the ultrasound probe into the non-welded construction; detecting ultrasound returns from the non-welded construction; feeding coolant into an internal volume of the probe via a coolant inlet of the probe during the passing of ultrasound; and removing coolant from the internal volume of the probe via a coolant outlet of the probe during the passing of ultrasound.

[0528] The method may comprise the preliminary step of providing the ultrasound probe and placing at least a section of a compliant element of an ultrasound probe in contact with an object constructed using metal additive manufacturing.

[0529] The method comprises locating the probe apparatus in proximity to the object under test. In the illustrated method, the method comprises locating the probe apparatus in contact with the object under test.

[0530] However, it will be understood that in alternative methods, the probe apparatus may be located adjacent to the object under test without contacting the object under test.

[0531] As in the method shown and described in Figure 27, in the method of Figure 29 the ultrasound probe comprises an axial element. The ultrasound emitting transducer is mounted on the axial element. Two or more support elements are rotatable mounted relative to the axial element. The compliant element is mounted on the two or more support elements and provides a continuous surface in at least one direction. The two or more support elements and the compliant element at least partially define the internal volume of the probe, the transducer being provided within the internal volume.

[0532] Figures 30 to 40 of the accompanying drawings illustrate a probe apparatus for implementing the methods of Figures 27 to 29.

[0533] Figure 30 shows a multiple axis robot 1007 with an arm 1009 on the distal end 1011 of which is a schematically illustrated probe 1013.

[0534] Figure 31 is a perspective view of an embodiment of a probe 1013. The axis of rotation R-R extends through the probe 1013. A first mounting location 1020 is provided lying on the axis, together with a second mounting location 1022 on the other side of the probe 1013. The first mounting location 1020 and the second mounting location 1022 provide for the mounting of the probe 1013 on the robot 1007 in a manner which allows for rotation of the probe 1013 as it is advanced over the surface of the object 1.

[0535] The probe 1013 has rigid end structures 1024a, 1024b at each end and these are provided with bolts 1025 to connect them and to provide an annular mounting 1026 for the generally cylindrical coupling element 1028.

[0536] Connected to the first mounting location 1020 and extending axially therefrom, is a manifold element 1030. The manifold element 1030 has a cooling fluid inlet 1032, which is connected in use to a cooling fluid feed conduit [not shown], and a cooling fluid outlet 1034, which is connected in use to a cooling fluid exit conduit [also not shown]. Figure 32 is a cross-sectional plan view of the probe of Figure 31 also showing many of the above features.

[0537] Referring to Figure 33, a cross-sectional side view of the probe of Figure 31 , the manifold element 1030 is fluidly connected to the first mounting location 1020. A first fluid connection is formed by first inlet bore section 1036 connecting to second inlet bore section 1038 which leads via a conduit 1040 to the internal volume 1042 of the probe 1013. A second fluid connection is formed by first outlet bore section 1044 connecting to a second outlet bore section [not shown] which leads from the internal volume 1042 of the probe 1013.

[0538] The internal volume 1042 extends between the opposing wall sections 1046a, 1046b of the coupling element 1028 and also extends between the opposing internal surfaces 1048a, 1048b of the rigid end structures 1024a, 1024b. The internal volume 1042, at least to a level above the maximum vertical extent 1050 of the transducer 1052, is filled with a coolant.

[0539] The coupling element 1028 is a unitary piece of compliant material, discussed further below. The coupling element 1028 is provided with generally right cylindrical main body part 1054 and with an inwardly turned rim 1056a, 1056b at the ends. The rims 1056a, 1056b are each compressed between an external element 1024a and an internal element 1024b which form the rigid end structure 1024a. The external element 1024a and opposing internal element 1024b are connected to one another by a series of releasable fasteners, in this case bolts 1025.

[0540] Thus, as the probe 1013 rolls over the surface of the object, different parts of the main body part 1054 of the coupling element 1028 contact the object and the external element 1024a and an internal element 1024b which form the rigid end structure rotate too.

[0541] The rigid end structure 1024a, 1024b is free to rotate relative to axial element 1064, a continuation of which provides the first mounting location 1020. A first shaft type seal 1066 and a second shaft type seal 1068 allow for the rotation whilst sealing against coolant leakage between the axial element 1064 and the rigid end structure 1024.

[0542] A second axial element 1070 is connected to the axial element 1064 by a series of releasable fasteners 1072. The second axial element 1070 provides a mounting for the transducer 1052, for an anti-echo block 1074 and a ultrasound conveying block 1076.

[0543] Thus, the transducer 1052, anti-echo block 1074 and conveying block 1076, together with the second axial element 1070, the axial element 1064 and the first mounting location 1020 do not rotate as the probe 1013 rolls over the surface of the object. Thus, the transducer 1070 and associated components are maintained in the same sensing orientation opposing the object, at all times.

[0544] As a result of the abovementioned configuration, when the probe 1013 rolls over the surface of the object, there is relative movement between the inside surface 1078 of the coupling element 1028 and the radial surface 1080 of the conveying block 1076.

[0545] Also mounted on the second axial element 1070 is a mounting element 1082 that carries a thermistor 1084 for temperature sensing of the internal roller probe domain at a location 1086 close to the part of the inside surface 1078 that abuts the object.

[0546] As seen in Figure 35 to 37, alternative embodiments of the probe 1013, transducer 1052 and conveying block 1076 can be provided. As shown in Figure 35, the transducer 1052 is mounted on an inclined, axial facing surface 1088 of the conveying block 1076 by means of fasteners 1092. The conveying block 1076 is provided with a coolant inlet 1093 and a coolant outlet 1094. As seen in Figure 36, the coolant inlet 1093 leads to a serpentine passageway 1095 and hence to a coolant feed outlet 1096 in fluid communication with the internal volume 1042 of the probe 1013. A similar structure on the other side of the conveying block 1076 extracts coolant from the internal volume, through a coolant withdrawal inlet, to a second serpentine passageway and hence to the coolant outlet 1094. These passageways and the configuration of these passageways assists with the cooling of the conveying block 1076.

[0547] The axial facing surface 1088 of the conveying block 1076 and / or the radial facing surface 1090 of the transducer 1052 can be provided with gaps, slots or grooves to aid coolant flow between the two surfaces.

[0548] For instance, referring to Figure 36, the inclined, axial facing surface 1088 has an intersection with a second axial facing surface 1097, which face 1097 is generally parallel to the axis of rotation. The transducer 1052 ends close to the intersection. As seen in the detail of Figure 36, a channel 1098, such as a groove, is provided in the conveying block 1076. The channel 1098 improves access for coolant to the gap 1092 between the axial facing surface 1088 of the conveying block 1076 and the radial facing surface 1090 of the transducer 1052. The channel 1098 is in fluid communication with a series further grooves 1099 in the axial facing surface 1088 of the conveying block 1076 to further promote coolant flow into the gap 1092. The channel 1098 and / or further channels 1099 could be provided in the transducer 1052 and / or in the conveying block 1076.

[0549] As seen in Figure 37 and the detailed view of Figure 37, the channel 1098 extends across the width of the conveying block 1076 from one side to the other. The further channels 1099 are regularly spaced along the channel 1098 and extend along the inclined, axial facing surface 1088 away from the channel 1098.

[0550] In another potential detail, the leading edge 1100 and the trailing edge 1102, considered relative to the rotation when the probe 1013 moves in direction A, of the conveying block 1076 are each provided with a chamfer. Thus, as the conveying block 1076 effectively moves through the coolant during rotation, the coolant is encouraged by the chamfer on the leading edge 1100 towards the gap 1108 between the radial facing surface 1080 of the conveying block 1076 and the inside surface 1078 of the coupling element 1028. This encourages the continuous presence of the coolant between the radial surface 1080 and the inside surface 1078, which is very beneficial for the passage of the ultrasound waves across the interface between the conveying block 1076 and the coupling element 1028. The continuous presence of the coolant is also helpful with cooling of the radial surface 1080 too.

[0551] The separation of the axis of rotation R-R and the object 1 being probed is such, in use, that the object 1 pushes the coupling element 1028 towards the axis and so into good contact with the conveying block 1076, with the coupling element 1028 being compressed between the object 1 and the conveying block 1076.

[0552] As can be seen in Figure 35, in another potential detail, the axial facing surface 1088 of the conveying block 1076 has a greater extent along the axis and perpendicular to the axis that the radial facing surface 1090 of the transducer 1052. As the conveying block 1076 and transducer 1052 are moved through the coolant by rotation of the probe 1013, this geometry encourages coolant into the junction between the conveying block 1076 and the transducer 1052 and so into the gap 1092 therebetween. The flow direction of the coolant into the device along conduit 1042 also promotes flow in the direction of the gap 1092.

[0553] In a still further potential detail, shown in Figure 38, the radial facing surface 1080 of the conveying block 1076 is provided with a series of interface channels 1300. These are recessed into the curved radial facing surface 1080 which faces the inside surface 1078 of the coupling element 1028 in use. The interface channels 1300 extend the full length of the conveying block 1076 and extend parallel to the axis, but other extents and profiles can be provided.

[0554] The continuous presence of the coolant in the gap 1092 between the axial facing surface 1088 of the conveying block 1076 and the radial facing surface 1090 of the transducer 1052 is very beneficial for the passage of the ultrasound waves across the interface between them.

[0555] With respect to the passage of ultrasound waves, the conveying block 1076 is fabricated from polyetherimide, as that offers the desired temperature resistance and capacity to deal with repeated cycles of temperature changes. Furthermore, the material has the necessary acoustic properties to be balanced with the other components.

[0556] For monitoring purposes, the thermistor 1084 is provided within a further block of polyetherimide, offset to the side of the conveying block 1076, so as not to interfere with the conveying block 1076 ultrasound propagation role. At the same time, the position of the thermistor 1084 is still effective in insuring that the temperature constraints of the components are not approached. If they are, then the probe 1013 can be removed from the object to prevent damage of the components. The block providing the thermistor 1084 may be attached to the conveying block 1076 in other embodiments, and the thermistor 1084 could be incorporated into the conveying block 1076 in other embodiments. With respect to the passage of ultrasound waves, the coupling element 1028 is a higher temperature compatible silicone rubber. The material selected is able to withstand temperatures in excess of 350°C for prolonged periods. Such materials can have an attenuation of 0.87dB / mm at 5Mhz and an acoustic impedance of 1.12 MRayls and so is a good alignment with the other materials employed. In terms of the thickness of the coupling element 1028, a balance is struck between increasing thickness giving more thermal insultation to the probe contents and increasing thickness causing detrimental increases in attenuation. A thickness of between 4mm and 8mm is suitable for such materials in the operating conditions under consideration.

[0557] The chosen materials for the coupling element 1028 also offer sufficient compliance for it to conform to the surface of the object under moderate applied force levels. High force levels are undesirable in terms of the equipment needed to generate them and still move the device over the test piece. A compliant material is needed to gain good contact for the transmission of the ultrasound, without undue loss, given that the surfaces of the objects encountered in real world situations are not highly finished or smooth.

[0558] With respect to the passage of ultrasound waves, the anti-echo block 1074 has an important role in preventing ultrasound waves bouncing within the probe and causing noise or other negative impacts upon the probe. Hydrogenated nitrile rubber, HNBR, was found to be a suitable material, particularly N filler forms thereof. This was due to the 6.4dB / mm attenuation provided at 5MHz.

[0559] All of these features serve to assist with successful acoustically coupling of the probe to the object through the real-world surface encountered.

[0560] To assist with the withstanding of the elevated surface temperatures of the object, the coolant circuit for the probe 1013 is used.

[0561] Figure 39 shows a schematic for the coolant circuit in one embodiment thereof. A coolant reservoir 1100 provides a coolant feed through conduit 1102 to pump 1104 and second conduit 1106 to the cooling fluid inlet 1032 provided on the probe 1013.

[0562] Within the internal volume 1042, the coolant is able to freely circulate within the full volume of that internal volume, including around the transducer 1052, around the conveying block 1076, through the gap therebetween, around the lower parts at least of the coupling element 1028 and through the gap 1092 between the coupling element 1028 and the radial facing surface 1080 of the conveying block 1076. Returning to Figure 39, from the internal volume 1042, the coolant exists through cooling fluid outlet 1034 and into a third conduit 1108. A temperature sensor in the third conduit and / or within the internal volume 1040 can be used to ensure cooling is as desired and potentially to control the pump speed to increase or decrease cooling. The third conduit 1108 leads to a heat exchanger 1110 which provides cooling of the coolant ready for reuse. The fourth conduit 1112 takes the cooled coolant from the heat exchanger 1110 and returns it to the reservoir 1100 ready for reuse.

[0563] The use of active cooling for the probe 1013 and its elements is beneficial in allowing the probe 1013 to be used on hot object surfaces for prolonged periods of time.

[0564] Referring to Figure 40, this shows a first temperature plot 1200 and a second temperature plot 1202, both against time that the probe in contact with the hot object. The first temperature plot 1200 is for a probe 1013 according to the disclosure and with circulating coolant. This shows that the approach is successful in maintaining the internal temperature of the probe 1013 well within operating limits. The active cooling provides ensures that the transducer is kept below the 55 to 60°C maximum operating temperatures applicable to most transducers of the desired type.

[0565] The second temperature plot 1202 is for a probe with similar internal components, but with the coolant volume fixed and limited to that sealed within the internal volume of the probe. The temperature clearly rises with time as heat transfers to the probe and builds up therein, until after a relatively short period of time, the temperature exceeds a reliable operating threshold of 50°C. In practice, such a probe would have to be removed from the object before that threshold of 50°C was reached and no monitoring could occur until the probe itself had cooled down.

[0566] In terms of the coolant, air offers poor thermal capacity and conductivity for active cooling. Water is also a sub-optimal as its acoustic impedance at at 1.5 MRayls is a poor match for the other components. Providing the coolant, in the form of a water-soluble oil, for instance which has an acoustic impedance of 1.1 MRayls and so is a better match with the acoustic impedance of the conveying block [1.1 or so MRayls],

[0567] The transducer 1052 provides a 5Mhz 64 element phased array and is mounted to generate 55° ultrasound waves into the object. A 0.5mm pitch and 10mm elevation can be used. An angled beam is beneficial in being able to inspect the object fully from a laterally spaced location. Frequently, that laterally spaced location will be more amenable to good contact between the probe and the object

[0568] This type of transducer and conveying block configuration can be used to provide a sectorial scan beam defined by the upper extremity beam [angled away from the perpendicular to the transducer face] and the lower extremity beam [near perpendicular to the transducer face] emitted.

[0569] In terms of the performance sought for the probe in terms of high temperature performance, the disclosure provides probes that are capable of inspecting for prolonged period objects that are at =300°C.

[0570] The coupling is dry but still achieves the necessary levels of ultrasound propagation through the interface into and back from the object.

[0571] The high-temperature polymer used in the coupling component is able to withstand prolonged contact with objects at such temperatures and still propagate the ultrasound to and from the interface successfully.

[0572] The coolant and hence the coolant filled gaps are able also to effectively propagate the ultrasound waves to and from the conveying block.

[0573] Optimal propagation properties for the conveying block are provided as the block is exposed to near ambient temperatures only and so there is no need to choose high temperature resistant materials which have lesser ultrasound propagation properties.

[0574] It will be understood that various modifications may be made without departing from the scope of the claimed invention.

Claims

CLAIMS1 . A probe apparatus for use in the non-destructive evaluation of an object under test, comprising: a transducer arrangement configured and / or operable to direct an ultrasonic beam towards the object under test; a compliant element configured to engage the object under test; and an intermediate member interposed between the transducer arrangement and the compliant element, wherein the intermediate member and the compliant element are arranged so as to define an interface therebetween, and wherein at least one of the intermediate member and the compliant element are configured and / or operable to retain a fluid disposed at the interface between the intermediate member and the compliant element.

2. The probe apparatus of claim 1 , wherein the configuration of the intermediate member and / or the compliant element so as to retain the fluid disposed at the interface comprises or takes the form of a surface treatment.

3. The probe apparatus of claim 2, wherein the surface treatment is formed or otherwise provided on a distal surface of the intermediate member.

4. The probe apparatus of claim 2 or 3, wherein the surface treatment comprises or takes the form of: one or more protrusions formed or otherwise provided on the intermediate member; one or more ridges formed or otherwise provided on the intermediate member; one or more grooves formed or otherwise provided on the intermediate member; one or more channels formed or otherwise provided on the intermediate member; and / or one or more bores formed or otherwise provided on the intermediate member.

5. The probe apparatus of claim 2, 3 or 4, wherein the surface treatment is formed by one or more of: milling, e.g. CNC milling;machining, e.g. laser machining; engraving; etching, e.g. acid etching; and / or sandblasting.

6. The probe apparatus of claim 2, 3 or 4, wherein a surface roughness Ra of the intermediate member is selected based on the wavelength A of the ultrasonic beam, and wherein Ra < A / 10.

7. The probe apparatus of any one of claims 2 to 6, wherein the surface treatment is formed or otherwise provided on a surface of the compliant element which faces the intermediate member.

8. The probe apparatus of claim 7, wherein the surface treatment comprises or takes the form of: one or more protrusions formed or otherwise provided on the compliant element; one or more ridges formed or otherwise provided on the compliant element; one or more grooves formed or otherwise provided on the compliant element; one or more channels formed or otherwise provided on the compliant element; and / or one or more bores formed or otherwise provided on the compliant element.

9. The probe apparatus of claim 7 or 8, wherein the surface treatment is formed by one or more of: milling, e.g. CNC milling; machining, e.g. laser machining; engraving; etching, e.g. acid etching; and / or sandblasting.

10. The probe apparatus of claim 7, 8 or 9, wherein a surface roughness Ra of the compliant element is selected based on the wavelength A of the ultrasonic beam, and wherein Ra < A / 10.

11. The probe apparatus of any preceding claim, wherein the transducer arrangement comprises one or a plurality of transducers.

12. The probe apparatus of claim 11 , wherein one or more of the transducers comprises or takes the form of: a piezoelectric transducer; an eddy current transducer; a capacitive transducer, e.g. a capacitive micro-machined ultrasonic transducer (CMUT); a dry-coupled ultrasonic test (DCLIT) transducer; and / or an electromagnetic acoustic transducer (EMAT).

13. The probe apparatus of claim 11 or 12, wherein the transducer arrangement comprises or takes the form of one or more transducer array.

14. The probe apparatus of claim 13, wherein one or more of the transducer arrays comprises or takes the form of a phased array ultrasonic transducer (PALIT) arrangement.

15. The probe apparatus of any preceding claim, wherein the intermediate member comprises or takes the form of a wedge.

16. The probe apparatus of any preceding claim, wherein the compliant element comprises or takes the form of a cylindrical or substantially cylindrical element.

17. The probe apparatus of any preceding claim, wherein the probe apparatus is configured so that the compliant element moves relative to the intermediate member.

18. The probe apparatus of claim 17, wherein the probe apparatus is configured so that the compliant element rotates around the intermediate member and / or the transducer arrangement, the compliant element comprising or taking the form of a rolling element, e.g. a tyre or a wheel.

19. The probe apparatus of any preceding claim, wherein the compliant element at least partially defines an internal volume, the transducer arrangement and / or the intermediate member disposed within the internal volume.

20. The probe apparatus of claim 19, wherein the probe apparatus is configured so that the compliant element moves axially relative to the intermediate member, the compliant element comprising or taking the form of a planar or substantially planar element, e.g. a membrane.

21. The probe apparatus of any preceding claim, comprising a support arrangement.

22. The probe apparatus of claim 21 , wherein the support arrangement comprises or takes the form of a mandrel.

23. The probe apparatus of any preceding claim, wherein the probe apparatus is configured and / or operable to control an angle of inclination of the compliant element so as to reduce a deviation in the ultrasonic beam propagating in the object under test.

24. A system for use in non-destructive evaluation of an object under test, comprising one or more of the probe apparatus according to any one of claims 1 to 23.

25. A method of non-destructive evaluation using the probe apparatus of any one of claims 1 to 23 or the system of claim 24.

26. A probe apparatus for use in the non-destructive evaluation of an object under test, comprising: a transducer arrangement configured and / or operable to direct an ultrasonic beam towards the object under test; a compliant element configured to engage the object under test; and an intermediate member interposed between the transducer arrangement and the compliant element, wherein the probe apparatus is configured and / or operable and / or is operatively associated with an arrangement to control an angle of inclination of the compliant element so as to reduce a deviation in the ultrasonic beam propagating in the object under test.

27. The probe apparatus of claim 26, wherein the probe apparatus comprises a passive arrangement for controlling the inclination of the compliant element.

28. The probe apparatus of claim 27, wherein the passive arrangement comprises one or more wheels.

29. The probe apparatus of claim 26, 27 or 28, wherein the probe apparatus is coupled to and / or operatively associated with an active arrangement for controlling the inclination of the compliant element.

30. The probe apparatus of claim 29, wherein the active arrangement comprises or takes the form of an actuator arrangement configured and / or operable to control the inclination of the compliant element.31 . A system for use in non-destructive evaluation of an object under test, comprising one or more of the probe apparatus according to any one of claims 26 to 30.

32. A method of non-destructive evaluation using the probe apparatus of any one of claims 26 to 30 or the system of claim 31.

33. A probe apparatus for use in the non-destructive evaluation of an object under test, wherein the probe apparatus comprises or takes the form of a roller probe, the probe apparatus comprising: a transducer assembly, wherein the transducer assembly comprises or takes the form of a transmit receive longitudinal (TRL) arrangement.

34. A probe apparatus for use in the non-destructive evaluation of an object under test, comprising: a transducer arrangement configured and / or operable to direct an ultrasonic beam towards the object under test, wherein the probe apparatus comprises or takes the form of a roller probe; and wherein the transducer arrangement comprises or takes the form of a matrix array.

35. A method for non-destructive evaluation of an object under test, wherein the object under test comprises or takes the form of a non-welded construction, the method comprising: emitting ultrasound into the object under test and receiving ultrasound back from the object under test, thereby acquiring multiple signal sets, including a first signal set and a second signal set; processing the first signal set and the second signal set to provide evaluation data relating to the object under test, wherein the first signal set comprises a first series of first data elements, the first series of data elements spanning a first time period, each first data element including a first variable value for a variable and a first time value for that first variable value, the first time period including a first time sub-period; the second signal set comprises a second series of second data elements, the second series of second data elements spanning a second time period, each second data element including a second variable value for the variable and a second time value for that second variable value, the second time period including a second time sub-period; the first time sub-period and the second time sub-period cover the same time values; the processing of the first signal set and the second signal set determining a modified signal set which contributes to the evaluation data, wherein the modified signal set: includes a modified time sub-period covering the same time values as the first time sub-period and the second time sub-period; and includes, for a time value, an expression of the first variable value for that time value and an expression of the second variable value for that time value, if the first variable value and the second variable value are within a given relationship to one another; and / or includes, for a time value, one of an expression of the first variable value for that time value or an expression of the second variable value for that time value, if the first variable value and the second variable value are not within a given relationship to one another.

36. The method of claim 35, wherein the method comprises the preliminary step of providing a probe apparatus and disposing the probe apparatus relative to the object under test so as to permit the probe apparatus to emit ultrasound into the object under test and receive ultrasound back from the object under test.

37. The method of claim 35 or 36, wherein the object under test comprises or takes the form of an object constructed using additive manufacturing techniques.

38. The method of claim 37, wherein the object under test comprises or takes the form of an object constructed using metal additive manufacturing.

39. The method of claim 38, wherein the object under test comprises or takes the form of an object constructed using wire arc additive manufacturing (WAAM).

40. The method of claim 35 or 36, wherein the object under test comprises or takes the form of a composite material.

41. The method of claim 35 or 36, wherein the object under test comprises or takes the form of a human or animal body.

42. The method of any one of claims 35 to 41, wherein the first variable value is an expression of amplitude.

43. The method of any one of claims 35 to 42, wherein the second variable value is an expression of amplitude.

44. The method of any of one of claims 35 to 43, wherein the first time period, second time period and / or one or more further time periods are the same duration.

45. A method for non-destructive evaluation of an object under test, wherein the object under test comprises or takes the form of non-welded construction, the method comprising: conducting the evaluation, wherein the object under test is provided at an elevated temperature state above ambient temperature by heating during the evaluation, the conducting of the evaluation comprising:emitting an ultrasound wave into a volume of the object under test; receiving at least a part of the ultrasound wave back from the object under test, thereby acquiring multiple signal sets; and processing one or more of the multiple signal sets to provide evaluation data relating to the object under test, wherein the processing includes a correction for temperature within the volume of the object under test at the elevated temperature.

46. The method of claim 45, wherein the method comprises the preliminary step of providing a probe apparatus and disposing the probe apparatus relative to the object under test so as to permit the probe apparatus to emit ultrasound into the object under test and receive ultrasound back from the object under test.

47. The method of claim 45 or 46, wherein the object under test comprises or takes the form of an object constructed using additive manufacturing techniques.

48. The method of claim 47, wherein the object under test comprises or takes the form of an object constructed using metal additive manufacturing.

49. The method of claim 48, wherein the object under test comprises or takes the form of an object constructed using wire arc additive manufacturing (WAAM).

50. The method of claim 45 or 46, wherein the object under test comprises or takes the form of a composite material.

51. The method of any one of claims 45 to 50, wherein the method comprises an elevated temperature which is consistent through the object under test and / or an elevated temperature which includes a temperature distribution in the object under test and / or probe apparatus.

52. The method of claim 51 , wherein the processing includes a correction for temperature distribution, within the volume of the object under test at the elevated temperature.

53. The method of claim 52, wherein the method provides that the correction includes, the path of at least a part of the ultrasound wave through probeapparatus and / or the volume of the object under test being corrected to give a corrected path.

54. A method for non-destructive evaluation of an object under test, wherein the object under test comprises or takes the form of non-welded construction the method including: providing an ultrasound probe comprising: an axial element; an ultrasound emitting transducer mounted on the axial element; two or more support elements rotatable mounted relative to the axial element; a compliant element, the compliant element being mounted on the two or more support elements and providing a continuous surface in at least one direction; wherein the two or more support elements and the compliant element at least partially define an internal volume for the probe, the transducer being provided within the internal volume; the probe further comprising an inlet for coolant to the internal volume and an outlet for coolant from the internal volume; the method further providing: placing at least a section of the compliant element in contact with the object under test; passing ultrasound from the transducer into the object under test and detecting ultrasound returns from the substrate, wherein coolant is fed into the internal volume via the coolant inlet and coolant is removed from the internal volume during the passing of ultrasound.

55. The method of claim 54, wherein the method comprises the preliminary step of providing a probe apparatus and disposing the probe apparatus relative to the object under test so as to permit the probe apparatus to emit ultrasound into the object under test and receive ultrasound back from the object under test.

56. The method of claim 54 or 55, wherein the object under test comprises or takes the form of an object constructed using additive manufacturing techniques.

57. The method of claim 56, wherein the object under test comprises or takes the form of an object constructed using metal additive manufacturing.

58. The method of claim 57, wherein the object under test comprises or takes the form of an object constructed using wire arc additive manufacturing (WAAM).

59. The method of claim 54 or 55, wherein the object under test comprises or takes the form of a composite material.

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