Machine and method for carrying out a hardness test

Abstract

The present invention relates to a machine (1) for carrying out a hardness test. This machine (1) comprises: an impression-generating station (2), a specimen handling and support station (3) and an impression-measuring station (4). The impression-generating station (2) comprises an indentor handling and support group (20) and an indentor group (21). The indentor group (21) comprises an indentor (210), a flange (211), and an indentor tang (212) extending between a first end (212') engaged with the indentor (210) and a second opposite end (212") engaged with the flange (211). The indentor handling and support group (20) is translatable along a vertical axis (V) and is engageable with the flange (211). The machine (1) is movable between an indentor movement configuration, in which the indentor handling and support group (20) is engaged with the flange (211), and a test run configuration, in which the indentor (210) is suitable for abutting with a specimen and the indentor handling and support group (20) is disengaged from the flange (211), so that the force applicable to the specimen depends only on the mass of the indentor group (21).

Description

DESCRIPTION" MACHINE AND METHOD FOR CARRYING OUT A HARDNESS TEST"

[0001] The present invention is in the technical field of machines for carrying out hardness tests.

[0002] The subject matter of the present invention is a machine for carrying out a hardness test, for example a Vickers hardness test, and a method for carrying out said test on a specimen.

[0003] The regulations governing the hardness test are known to a person skilled in the art. In particular:

[0004] - the standard EN ISO 6506 governs the Brinell hardness test;

[0005] - the standard EN ISO 6507 governs the Vickers hardness test;

[0006] - the standard EN ISO 6508 governs the Rockwell hardness test.

[0007] To date, hardness tests are carried out by making an impression on a specimen. Once the impression step is completed, an operator takes the specimen and moves to a measuring machine in order to measure the impression. For example, in the case of a Vickers hardness test, the measuring machine allows a first diagonal and a second diagonal of the impression to be measured.

[0008] It is obvious that carrying out a hardness test according to the prior art requires the presence of aqualified operator.

[0009] In addition, at least two machines are required to complete the test, namely an indentation machine equipped with an indentor to produce the impression and a measuring machine to measure the impression obtained.

[0010] Disadvantageously, hardness tests conducted in accordance with the prior art are extremely expensive in terms of both human resources, as they require the active presence of qualified operators, and equipment, as at least two machines are required.

[0011] The object of the present invention is to propose a machine and a method for carrying out a hardness test that are capable of overcoming, at least in part, the drawbacks mentioned above.

[0012] In particular, it is the object of the present invention to propose an automatic machine and a related method which do not require the presence of an operator, with the exception of the supervision and positioning of the specimen on the machine itself.

[0013] Said object is achieved with a machine according to claim 1 and with a method according to claim 12. The dependent claims describe preferred embodiments of the invention.

[0014] The features and advantages of the machine and method according to the invention shall be made readilyapparent from the following description of preferred exemplary embodiments thereof, provided purely by way of non-limiting example, with reference to the accompanying figures, wherein:

[0015] - Fig. 1 is a perspective view of a machine in accordance with the present invention;

[0016] - Fig. 2 is a perspective view of an impression-generating station;

[0017] - Fig. 2a is a side view of the impression-generating station in Fig. 2;

[0018] - Fig. 2b is a front view of the impression-generating station of Fig. 2;

[0019] - Fig. 2c is a cross-sectional view taken along the line II-II of Fig. 2b;

[0020] - Fig. 3 is an exploded perspective view of a specimen handling and support station.

[0021] In said drawings, the numerical reference 1 indicates a machine for carrying out a hardness test on a specimen according to the invention as a whole.

[0022] Preferably, this machine 1 is suitable for carrying out a Vickers hardness test.

[0023] For the purposes of this discussion, it is specified that the terms "horizontal," "vertical," "lower," "upper," "above, " "below," "downward," "upward" and the relative derivatives thereof are to be understood asreferring to the machine 1 under operating conditions unless otherwise specified.

[0024] The machine 1 comprises: an impression-generating station 2, a specimen handling and support station 3 and an impression-measuring station 4.

[0025] The impression-generating station 2 is suitable for generating an impression on the specimen.

[0026] The specimen handling and support station 3 is suitable for moving and supporting the specimen.

[0027] The impression-measuring station 4 is suitable for identifying a region of the specimen where the hardness test is to be carried out and is suitable for measuring the impression generated on the specimen.

[0028] The impression-generating station 2 comprises an indentor handling and support group 20 and an indentor group 21.

[0029] The indentor group 21 comprises an indentor 210 extending along an indentor axis P, a flange 211, and an indentor tang 212 extending between a first end 212' engaged with the indentor 210 and a second end 212" opposite the first end 212' and engaged with the flange 211.

[0030] In particular, the indentor tang 212 is integrally engaged with both the indentor 210 and the flange 211.

[0031] Preferably, the flange 211 is a plate that extendsradially with respect to the indentor axis P.

[0032] The indentor handling and support group 20 is translatable along a vertical axis V and is engageable with the flange 211.

[0033] The machine 1 is movable between an indentor movement configuration and a test run configuration. In the indentor movement configuration, the indentor handling and support group 20 is engaged with the flange 211; on the other hand, in the test run configuration, the indentor 210 is suitable for being in contact with the specimen, and the indentor handling and support group 20 is disengaged from the flange 211. Therefore, with the machine 1 in the test run configuration, the force applicable to the specimen depends only on the mass of the indentor group 21 and optionally on the mass of a ballast 213 positioned on the flange 211.

[0034] In one embodiment, the indentor group 21 comprises, preferably consists of, the indentor 210, the flange 211, the indentor tang 212 and, optionally, the ballast 213. The mass of the indentor group 21 therefore coincides with the sum of the masses of the indentor 210, the flange 211, the indentor tang 212 and optionally the ballast 213 positioned on the flange 211.

[0035] The standard for the Vickers hardness test provides for a progressive increase in the force applied to thespecimen; therefore, the indentor group 21 also comprises the ballast 213 if it is necessary to perform ballasted hardness tests. In particular, the standard provides for starting from a mass of 20 g, which exactly corresponds to the sum of the masses of the indentor 210, flange 211 and indentor tang 212. Subsequently, the increase in force acting on the specimen is obtained by placing the appropriate ballast 213 on the flange 211.

[0036] According to the embodiment illustrated in the attached Fig. 3, the specimen handling and support station 3 comprises a support 30 suitable for acting as a support base for the specimen, and means 31 for positioning the specimen.

[0037] In particular, these specimen positioning means 31 comprise: a first positioning actuator 311, a second positioning actuator 312 and a third positioning actuator 313.

[0038] The first positioning actuator 311 allows the support 30 to be moved along a first horizontal axis X.

[0039] The second positioning actuator 312 allows the support 30 to be moved along a second horizontal axis Y.

[0040] The third positioning actuator 313 allows the rotation of the support 30 about a third vertical axis Z.

[0041] According to one embodiment, the support 30 is of the pneumostatic type.

[0042] In particular, the support 30 is a pneumostatic guide provided in its center with a core 33 that acts as a support base for the specimen. Such a pneumostatic guide makes use of air to reduce (preferably almost cancel) the friction of the core 33 and have only the mass of the indentor group 21 act on the specimen, without being altered by the friction. In other words, the friction of the core 33 does not affect the force applicable to the specimen.

[0043] According to one embodiment, the machine 1 further comprises a fourth positioning actuator 5 engaged with the specimen handling and support station 3. This fourth positioning actuator 5 allows the specimen handling and support station 3 to be moved along a third horizontal axis X'.

[0044] Preferably, the third horizontal axis X' is parallel to the first horizontal axis X or to the second horizontal axis Y.

[0045] The fourth positioning actuator 5 makes it possible to arrange the specimen handling and support station 3 so that it faces the impression-measuring station 4 or the impression-generating station 2.

[0046] According to an embodiment shown in the attached Fig. 2-2c, the indentor handling and support group 20 comprises a lower support element 200 engageable with theflange 211.

[0047] With the machine 1 in the indentor movement configuration, the lower support element 200 engages the flange 211 so as to support the indentor group 21 in translation along the vertical axis V.

[0048] On the other hand, with the machine 1 in the test run configuration, the lower support element 200 is disengaged from the flange 211 and is arranged at a different height than the height of the flange 211.

[0049] Therefore, in the test run configuration, the lower support element 200 is not in contact with the indentor group 21 and therefore does not offer any support to said indentor group 21.

[0050] It should be noted that the height is a measurement of the height measured along the vertical axis V starting from a base plane.

[0051] Preferably, when the machine 1 is in the test run configuration, the lower support element 200 is positioned at a lower height than that of the flange 211. Therefore, in the test run configuration, the indentor 210 abuts with the specimen and the indentor handling and support group 20 continues the translation downward along the vertical axis V, so as to disengage the lower support element 200 from the flange 211.

[0052] In one embodiment, the lower support element 200comprises a plurality of lower arms, preferably three angularly evenly spaced lower arms, oriented radially toward the indentor axis P. Preferably, the lower support element 200 is configured as a lower spider, similar to a washing machine spider.

[0053] According to one embodiment, the indentor handling and support group 20 comprises an upper support element 201 and at least one rod 202 that connects the aforesaid upper support element 201 to the lower support element 200.

[0054] Preferably, the at least one rod 202 is three rods.

[0055] For example, the upper support element 201 comprises a plurality of upper arms, preferably three angularly evenly spaced upper arms, oriented radially toward the vertical axis V. In this case, the upper support element 201 is configured as an upper spider, similar to the washing machine spider.

[0056] In particular, the lower support element 200, the upper support element 201 and the at least one rod 202 form a kind of "basket" to support the indentor group 21 in the translation along the vertical axis V between the indentor movement configuration and the test run configuration.

[0057] According to one embodiment, the indentor handling and support group 20 also comprises an actuation group203 which controls the translation of the indentor handling and support group 20 along the vertical axis V.

[0058] In particular, the actuation group 203 comprises:

[0059] - a gearmotor group 205 comprising a motor and a reduction gear;

[0060] - a translatable member 206 movable along the vertical axis V and operatively connected to the upper support element 201. For example, the translatable member 206 is a ball screw; and

[0061] - motion transmission means 207 connecting the gearmotor group 205 to the translatable member 206.

[0062] Therefore, the translatable member 206 allows the upper 201 and lower 200 support elements and the at least one rod 202 connecting them to translate vertically.

[0063] Finally, it should be noted that the motion transmission means 207 comprise:

[0064] - a driving pulley 207a keyed to a shaft of the gearmotor group 205;

[0065] - a driven pulley 207b operatively engaged with the translatable member 206; and

[0066] - a motion return member 207c which connects the driving pulley 207a to the driven pulley 207b. For example, the motion return member 207c is a belt.

[0067] According to one embodiment, the impression-measuring station 4 comprises a microscope 40 equippedwith at least one lens 400, a camera 41 and a control unit configured to store the impression positioning coordinates and to measure said impression.

[0068] Preferably, the microscope 40 is an optical microscope.

[0069] In particular, in the case of the Vickers hardness test, the indentor 210 generates the impression on the specimen and the control unit is configured to calculate a first diagonal and a second diagonal of the impression.

[0070] With the impression entering the visual field of the microscope 40, the control unit is configured to measure it directly, e. g., the lens 400 is commanded by the control unit to perform a direct digital measurement of the impression.

[0071] In one embodiment, with the impression obtained from a Vickers hardness test exiting the visual field of the microscope 40, the specimen handling and support station 3 is translatable between a first diagonal end measurement position, in which a first end of a diagonal of the impression is observable in the visual field, and a second diagonal end measurement position, in which a second end of the diagonal of the impression is observable in the visual field.

[0072] In particular, in the first diagonal end measurement position, the first end of the diagonal of the impressionis positioned on the optical axis of the microscope 40. On the other hand, in the second diagonal end measurement position, the second end of the diagonal of the impression — which is linearly opposed to the first end — is positioned on the optical axis of the microscope 40.

[0073] The impression-measuring station 4 also comprises a first impression-measuring device 42, for example a first laser meter. In this case, the first impression-measuring device 42 is capable of emitting a laser beam.

[0074] Furthermore, the specimen handling and support station 3 comprises a measurement abutment 32 which, cooperating with the first impression-measuring device 42, allows the length of the diagonal to be measured, which is proportional to the distance between the first diagonal end measurement position and the second diagonal end measurement position.

[0075] In particular, the term "diagonal of the impression" means the first or second diagonal of the impression.

[0076] Preferably, the measurement abutment 32 is a target capable of reflecting the laser beam emitted by the first impression-measuring device 42.

[0077] The translation of the specimen handling and support station 3 is controlled by the fourth positioning actuator 5.

[0078] In particular, the diagonal of the impression isarranged parallel to the third horizontal axis X' and the first end of the diagonal is observed (by focusing on it) with the microscope 40. Subsequently, the specimen handling and support station 3 translates until the second end of the diagonal is visible in the visual field of the microscope 40. The first impression-measuring device 42 measures the length of the diagonal by calculating the difference between the distances measured at the first end and the second end of the diagonal.

[0079] In this case, the measurement abutment 32 reflects the laser beam emitted by the first impression-measuring device 42 and thus makes it possible to detect the measurement of the distance between the first impressionmeasuring device 42 and the measurement abutment 32. Therefore, the length of the diagonal is proportional to the difference in the distances measured at the first end and at the second end of the diagonal.

[0080] Preferably, the first impression-measuring device 42 operates parallel to the third horizontal axis X'. In particular, the laser beam is parallel to said third horizontal axis X'.

[0081] According to one embodiment, the impressionmeasuring station 4 also comprises a second impressionmeasuring device 43, for example a second laser meter (e. g., a laser distance meter), suitable for measuringthe speed of the indentor 210 and / or the depth of the impression. This second impression-measuring device 43 operates parallel to the vertical axis V.

[0082] In particular, the second impression-measuring device 43 operates along the vertical axis V.

[0083] The vertical axis V is parallel to and preferably collinear with the indentor axis P.

[0084] In particular, the second impression-measuring device 43 comprises a laser emitter and a mirror suitable for orienting the laser beam parallel to the vertical axis V. The flange 211 of the indentor group 21 is mirror-polished so as to reflect the laser beam emitted by the second impression-measuring device 43.

[0085] It is well known to a person skilled in the art that the Martens hardness test, which has not yet been standardized, provides for the acquisition of data relating to the depth of the impression and to the displacement and speed of the indentor 210 during the execution of the impression. These data may be acquired by means of the second impression-measuring device 43. Therefore, the machine 1 that is the subject of the present invention is also suitable for carrying out Martens hardness tests.

[0086] In one embodiment, the indentor handling and support group 20 also comprises a guide 204 where the indentorgroup 21 is at least partially housed. This guide 204 is made of graphite, so as to reduce (and preferably almost cancel) the friction between the aforesaid guide 204 and the indentor group 21.

[0087] Preferably, the guide 204 is hollow-cylindrical in shape.

[0088] The indentor group 21 is at least partially housed within the guide 204 in a sliding manner along the vertical axis V.

[0089] In this case, the indentor tang 212 is housed in the guide 204.

[0090] The guide 204 is an air guide made of graphite. As is known, graphite is porous and is a self-lubricating material that allows air to pass through. The air creates an opening at the interface with the indentor group 21 (in particular with the indentor tang 212), so as to reduce friction and to ensure that the weight of the indentor group 21 is exactly 20 g (20 g coincides with the sum of the masses of the indentor 210, flange 211 and indentor tang 212 in the case of a non-ballasted Vickers hardness test).

[0091] Experimentally, it has been observed that any other guide — other than the guide 204 used for the purposes of the present invention — would cause an increase in the weight of the indentor group 21 due to a non-optimalreduction in friction between the guide and the indentor group 21.

[0092] For the purposes of the present invention, a method for carrying out a hardness test, such as a Vickers hardness test, is also proposed.

[0093] Preferably, this method is completely automated insofar as it does not require the active presence of an operator except for the positioning of the specimen on the machine 1 and the supervision of the operation of the machine itself.

[0094] The method comprises the steps indicated below.

[0095] The machine 1 and a specimen to be placed on the specimen handling and support station 3 are prepared.

[0096] The specimen is moved so that it faces the impression-measuring station 4. In particular, the specimen faces the microscope 40.

[0097] A region of the specimen is identified where the hardness test (preferably a Vickers hardness test) is to be carried out, and the coordinates of said region are stored. In particular, the control unit is configured to identify, acquire and store the coordinates of the region of the specimen to be subjected to the hardness test.

[0098] The specimen is moved in such a way that it faces the impression-generating station 2 and the hardness test is carried out. In other words, the specimen ispositioned under the indentor 210 so that the hardness test may be carried out.

[0099] Once the hardness test has been completed, the specimen is moved in such a way that the region of the specimen where the hardness test was carried out is facing the impression-measuring station 4. In particular, the control unit — which has previously stored the coordinates of said region — controls the fourth positioning actuator 5 in order to ensure that the identified region faces the microscope 40.

[0100] Finally, the impression is measured.

[0101] In one embodiment of the method, the performance of the hardness test comprises the following sub-steps.

[0102] The machine 1 is arranged in an indentor movement configuration, so that the indentor handling and support group 20 is engaged with the flange 211 and the indentor group 21 is raised vertically along the vertical axis V.

[0103] Preferably, to correct any misalignments, the specimen handling and support station 3 allows the specimen to be aligned with the indentor 210 through the actuation of the first 311 and / or the second 312 and / or the third positioning actuator 313.

[0104] The indentor group 21 is lowered until theindentor 210 abuts against the specimen.

[0105] The vertical downward motion continues until the indentor handling and support group 20 is disengaged from the flange 211 and the machine 1 is arranged in the test run configuration. Therefore, when the machine 1 is in the test run configuration, the flange 211 is at a higher height than the height of the lower support element 200.

[0106] It is evident that the fourth positioning actuator 5 allows the specimen handling and support station 3 to be moved in order to make the specimen face (placed under) the microscope 40 or the indentor 210.

[0107] Preferably, in order to carry out a ballast hardness test — wherein the mass applied to the specimen does not depend only on the sum of the masses of the indentor 210, flange 211 and indentor tang 212 — a ballast 213 is placed on the flange 211, the machine 1 is arranged in the test run configuration, and the hardness test is carried out.

[0108] According to an embodiment of the method, the impression-measuring station 4 also comprises the microscope 40 and the first impression-measuring device 42. Furthermore, the specimen handling and support station 3 comprises the measurement abutment 32. The impression-measuring step is performed directly with themicroscope 40, in particular if the impression is entirely contained within a visual field of the microscope 40.

[0109] Alternatively, if the impression exits the visual field of the microscope 40, the impressionmeasuring step comprises the following sub-steps.

[0110] The specimen handling and support station 3 is translated into a first diagonal end measurement position, where a first end of a diagonal of the impression is observable in the visual field. Preferably, the first end of the diagonal of the impression is positioned on the optical axis of the microscope 40.

[0111] The distance between the first impressionmeasuring device 42 and the measurement abutment 32 is measured when the specimen handling and support station 3 is in the first diagonal end measurement position.

[0112] The specimen handling and support station 3 is translated into a second diagonal end measurement position, where a second end of the diagonal of the impression is observable in the visual field. Preferably, the second end of the diagonal of the impression is positioned on the optical axis of the microscope 40.

[0113] The distance between the first impressionmeasuring device 42 and the measurement abutment 32 is measured when the specimen handling and support station 3is in the second diagonal end measurement position.

[0114] The length of the diagonal is measured as the difference between the measurement associated with the first diagonal end measurement position and the measurement associated with the second diagonal end measurement position.

[0115] In particular, the sub-steps for measuring the impression are performed for both the first and the second diagonal of the impression.

[0116] In one embodiment of the method, the impression-measuring station 4 also comprises the second impression-measuring device 43. The step of carrying out the hardness test therefore also comprises the following sub-steps.

[0117] The speed of the indentor 210 is measured. Preferably, in addition to the speed, the displacement of the indentor 210 is also measured. The speed of the indentor 210 is measured during the translation from the indentor movement configuration to the test run configuration. Therefore, the speed of the indentor 210 is also measured during the indentation of the specimen.

[0118] The impression depth is measured.

[0119] In particular, the second impression-measuring device 43 operates along the vertical axis V. Said second impression-measuring device 43 comprises the laseremitter and the mirror suitable for orienting the laser beam parallel to the vertical axis V. The flange 211 of the indentor group 21 is mirror-polished so as to reflect the laser beam emitted by the second impression-measuring device 43.

[0120] Therefore, the second impression-measuring device 43 makes it possible to measure both the speed (and also the displacement) of the indentor 210 and the depth of the impression. Furthermore, the force applied to the specimen is known and the control unit is configured to detect the time taken to carry out the hardness test.

[0121] Innovatively, the machine and the method according to the present invention achieve the intended object.

[0122] Advantageously, the machine that is the subject of the present invention allows a hardness test to be carried out more rapidly than the solutions currently offered by the prior art.

[0123] Advantageously, moreover, the method for carrying out a hardness test according to the present invention is quicker and faster than the other currently known test execution methodologies.

[0124] According to an advantageous aspect, the machine not only makes it possible to carry out thehardness test but also integrates the impressionmeasuring station, making it possible to directly measure the impression on board the machine.

[0125] A further advantage of the machine that is the subject of the present invention is that it is completely automatic. In fact, the operator has only the task of positioning the specimen on the machine, after which the hardness test is carried out by the machine completely independently, only with the supervision of the operator, but without the direct involvement of the operator.

[0126] According to an advantageous aspect, the method for carrying out the hardness test is more economical than that which is contemplated by the prior art, because the use of a completely automatic machine makes it possible to optimize the process for carrying out the test and measuring the impression, thus saving on manhours.

[0127] A person skilled in the art may make changes to the embodiments of the machine and the method in order to meet contingent requirements or may replace elements with other functionally equivalent ones. These variants are also contained within the scope of protection as defined by the following claims. Furthermore, each of the variants described as belonging to a possible embodiment may be obtained independently in the other describedembodiments.

Claims

CLAIMS1. A machine (1) for performing a hardness test on a specimen, said machine (1) comprising:- a print generating station (2) suitable for generating a print on the specimen;- a specimen movement and support station (3) suitable for moving and supporting the specimen;- a print measuring station (4) suitable for identifying a region of the specimen where to perform the hardness test and suitable for measuring the print generated on the specimen,wherein the print generating station (2 ) comprises an indenter movement and support group (20) and an indenter group (21), said indenter group (21) comprising an indenter (210) extending along an indenter axis (P), a flange (211), and an indenter tang (212) extending between a first end (212' ) engaged with the indenter (210) and a second opposite end (212") engaged with the flange (211), andwherein the indenter movement and support group (20) is translatable along a vertical axis (V) and is engageable with the flange (211),said machine (1 ) being movable between an indenter movement configuration, in which the indenter movementand support group (20) is engaged with the flange (211) and a testing configuration, in which the indenter (210) is suitable for being in contact with the specimen and the indenter movement and support group (20) is disengaged from the flange (211), so that the force applicable to the specimen depends only on the mass of the indenter group (21) and optionally on the mass of a ballast (213) positioned on the flange (211).

2. Machine (1) according to the preceding claim, wherein the specimen movement and support station (3) comprises a support (30) suitable for acting as a support base for the specimen and specimen positioning means (31), in particular said specimen positioning means (31) comprising:- a first positioning actuator (311) for moving the support (30) along a first horizontal axis (X);- a second positioning actuator (312) for moving the support (30) along a second horizontal axis (Y);- a third positioning actuator (313) for rotating the support (30) about a third vertical axis (Z).

3. Machine (1) according to the preceding claim, wherein the support (30) is of the pneumostatic type.

4. Machine (1) according to any one of the preceding claims, further comprising a fourth positioning actuator (5) engaged with the specimen movement and supportstation (3), said fourth positioning actuator (5) moving the specimen movement and support station (3) along a third horizontal axis (X' ).

5. Machine (1) according to any one of the preceding claims, wherein the indenter movement and support group (20) comprises a lower support element (200) engageable with the flange (211), and whereinwith the machine (1) in the indenter movement configuration, the lower support element (200) engages the flange (211) so as to support the indenter group (21) during the translation along the vertical axis (V), and with the machine (1) in the testing configuration, the lower support element (200) is disengaged from the flange (211) and is arranged at a different height from the height of the flange (211).

6. Machine (1) according to the preceding claim, wherein the indenter movement and support group (20) comprises an upper support element (201) and at least one rod (202) connecting said upper support element (201) to the lower support element (200).

7. Machine (1) according to the preceding claim, wherein the indenter movement and support group (20 ) also comprises an actuating group (203) which controls the translation of said indenter movement and support group (20) along the vertical axis (V).

8. Machine (1) according to any one of the preceding claims, wherein the print measuring station (4) comprises a microscope (40 ) provided with at least one objective (400), a camera (41), and a control unit configured to store the positioning coordinates of the print and measure said print.

9. Machine (1) according to the preceding claim, wherein, with the print exiting a field of view of the microscope (40), the specimen movement and support station (3) is translatable between a first diagonal endpoint measuring position, in which a first endpoint of a diagonal of the print is observable in the field of view, and a second diagonal endpoint measuring position, in which a second endpoint of the diagonal of the print is observable in the field of view,wherein the print measuring station (4) also comprises a first print measuring device (42), for example a first laser meter, andwherein the specimen movement and support station (3) comprises a measuring abutment (32) which, cooperating with the first print measuring device (42), allows measuring the length of the diagonal, said length of the diagonal being proportional to the distance between the first diagonal endpoint measuring position and the second diagonal endpoint measuring position.

10. Machine (1) according to any one of the preceding claims, wherein the print measuring station (4) also comprises a second print measuring device (43), for example a second laser meter, suitable for measuring the speed of the indenter (210) and / or the depth of the print, said second print measuring device (43) operating parallel to the vertical axis (V).

11. Machine (1) according to any one of the preceding claims, wherein the indenter movement and support group (20) also comprises a guide (204), the indenter group (21) being at least partially housed inside said guide (204), said guide (204) being made of graphite so as to reduce the friction between the guide (204) and the indenter group (21).

12. A method for performing a hardness test, said method comprising the following steps:- providing a machine (1) according to any one of the preceding claims and a specimen to be arranged on the specimen movement and support station (3);- moving the specimen so that it faces the print measuring station (4);- identifying a region of the specimen where to perform the hardness test and storing the coordinates of said region;moving the specimen so that it faces the printgenerating station (2) and performing the hardness test; - upon completing the hardness test, moving the specimen so that the region of the specimen where the hardness test has been performed faces the print measuring station (4);- measuring the print.

13. Method according to the preceding claim, wherein performing the hardness test comprises the following substeps:- arranging the machine (1) in the indenter movement configuration so that the indenter movement and support group (20) is engaged with the flange (211) and the indenter group (21) is vertically lifted along the vertical axis (V);- lowering the indenter group (21) to bring the indenter (210) to abut against the specimen;- continuing with the vertical downward motion until the indenter movement and support group (20) is disengaged from the flange (211) and arranging the machine (1) in the testing configuration.

14. Method according to claim 12 or 13, wherein the print measuring station (4) comprises a microscope (40) and a first print measuring device (42), and wherein the specimen movement and support station (3) comprises a measuring abutment (32), andwherein the print measuring step is performed with the microscope (40); orif the print exits a field of view of the microscope (40), the print measuring step comprises the following sub-steps:- translating the specimen movement and support station (3) to a first diagonal endpoint measuring position, where a first endpoint of a diagonal of the print is observable in the field of view;- measuring the distance between the first print measuring device (42) and the measuring abutment (32) when the specimen movement and support station (3) is in the first diagonal endpoint measuring position;- translating the specimen movement and support station (3) to a second diagonal endpoint measuring position, where a second endpoint of the diagonal of the print is observable in the field of view;- measuring the distance between the first print measuring device (42) and the measuring abutment (32) when the specimen movement and support station (3) is in the second diagonal endpoint measuring position;- measuring the length of the diagonal as the difference between the measurement associated with the first diagonal endpoint measuring position and the measurement associated with the second diagonal endpoint measuringposition.

15. Method according to any one of claims 12 to 14, wherein the print measuring station (4) comprises a second print measuring device (43), the step of performing the hardness test also comprises the following sub-steps:- measuring the speed of the indenter (210);- measuring the depth of the print.

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