Step sample

Abstract

A bearing sample (70) comprising a component (71) made of a metallic or composite material and having a cavity extending along its entire length, the bearing sample (70) comprising an elastomeric layer (72) intended to receive at least partially said component (71) so as to form a contact interface (73), the bearing sample (70) being characterized in that the component (71) is divided from one end to the other along a predetermined axis, forming two distinct parts (P1, P2). Figure for the abbreviation: Fig. 3A

Description

Title of the invention: Bearing sample technical field

[0001] The present exposition relates to a step sample, a method, a computer program, and a device for determining a resistance to separation and a percentage of adhesion between components of such a step sample.

[0002] The bearing sample may correspond to a prototype of a stabilizer bar bearing in any type of vehicle, in order to limit vehicle roll. It is obvious to those skilled in the art that this bearing is not specifically limited to a single application, such as stabilizer bars for vehicles. On the contrary, this type of bearing could be used in various industrial and mechanical applications where a bond between metallic or composite components and an elastomer layer (a constituent element of the bearing) is required. Previous technique

[0003] In a vehicle with axles, the two wheels of the same axle are generally connected by a stabilizer bar. The stabilizer bar, also called an anti-roll bar, is a suspension component of the vehicle. This bar acts as a spring that connects the two wheels of the same axle. It thus reduces body roll during cornering and dampens the deformations experienced by the suspension, in order to maintain optimal contact between the tires of said wheels and the road surface, ensuring maximum grip.

[0004] Each end of the stabilizer bar is thus fixed to the suspension triangle of a wheel, by means of ball-jointed links, while its central part is fixed to the chassis of the vehicle using at least two bearings.

[0005] These bearings are designed to allow the stabilizer bar to be fixed to the vehicle chassis while offering some flexibility, the stabilizer bar needing to be able to move slightly relative to the chassis.

[0006] For this purpose, the bearings generally comprise a metal flange and an elastic ring interposed between the stabilizer bar and the flange. This elastic ring, often made of elastomer, is thus generally placed around the stabilizer bar and then clamped by the flange, creating a compression that holds the ring in place.

[0007] The adhesion between the elastic ring and the stabilizer bar plays a crucial role in the effective operation of the vehicle's suspension system. This adhesion is achieved through several mechanisms that come into play during the installation and operation of the part. First, during installation, the elastic ring is The bushing is positioned around the stabilizer bar (also called the sway bar), where it is subjected to compression when clamped by the metal flange, as explained above. This compression creates friction between the bushing and the bar, ensuring a firm bond between the two components. Secondly, this installation process involves the use of special glues or adhesives to reinforce the bond between the bushing and the stabilizer bar. These glues / adhesives are chosen for their adhesion properties to both the elastomer of the bushing and the material of the stabilizer bar.

[0008] However, if the elastic ring is not properly bonded to the stabilizer bar, it may deform or crack prematurely, which can lead to bearing failure. Furthermore, this insufficient bonding is likely to cause unwanted slippage or movement between the elastic ring and the stabilizer bar, generating significant noise.

[0009] Furthermore, if the protective coating usually applied to the stabilizer bar peels off due to poor bonding of the elastic bushing, blisters appear in the paint, which can then flake off, weakening the corrosion barrier normally provided by the paint. Road contaminants, particularly dust and water spray, can then seep under the paint at the bearing and cause localized corrosion of the stabilizer bar. This corrosion, combined with the stresses exerted by the bearing on the stabilizer bar, leads to deterioration of the paint right up to the elastic bushing.

[0010] As a result, in addition to this corrosion problem, this phenomenon causes significant noise, as the bearing then rubs against an area of ​​damaged paint or even directly against the exposed and corroded stabilizer bar.

[0011] For the sake of clarity, it should be noted that noise refers to unwanted sounds or excessive friction noises between the bearing and the surface of the stabilizer bar. For a driver, the noise generated can be extremely bothersome for several reasons. Indeed, friction (sliding) or squeaking noises can make the journey uncomfortable for the driver. The driving experience is then unpleasant, especially over long distances. This phenomenon is particularly noticeable during the winter months, when the polymer constituting the elastic bushing hardens due to lower temperatures. Thus, when the polymer hardens, it increases the risk of friction or squeaking, thereby amplifying the noises perceived inside the vehicle.

[0012] Thus, an uncomfortable driving experience can then lead to a negative perception of the quality of the vehicle by the driver, and this can result in a decrease in customer satisfaction.

[0013] The adhesion between the elastic ring and the stabilizer bar is therefore essential to ensure the proper functioning and safety of the vehicle's suspension system.

[0014] To guarantee the quality and reliability of the adhesion between the elastic ring and the stabilizer bar, equipment manufacturers use specific tests, one of the most common being the ASTM D429 test. This test is widely known in the industry for evaluating the adhesion properties of elastomeric materials with substrates, generally metallic, thus providing an indication of an adhesive's ability to maintain a durable bond between these two surfaces. It therefore allows equipment manufacturers, particularly those specializing in the manufacture of suspension systems, to verify the conformity of their products to the quality and safety standards established by the industry.

[0015] The ASTM D429 test generally involves the preparation of standardized samples (bearing samples) comprising the elastomer and a substrate, usually metallic, similar to those used in stabilizer bar bearings. These samples, whose dimensions differ from, or even significantly differ from, those of the stabilizer bar bearing intended for operational use, are then subjected to controlled test conditions, such as mechanical and thermal stresses. By measuring the forces required to separate the elastomer from the substrate, usually metallic, this test makes it possible to evaluate the effectiveness of the adhesive and the strength of the bond.

[0016] This test evaluates, for example, the resistance of an adhesive to a push force between the substrate, generally metallic, and the elastomer material. In this case, the test involves applying a push force to progressively separate the elastomer from the substrate, thus measuring the force required to cause the adhesive to fail.

[0017] Push-off force is also referred to in industry jargon as "push-off" and can be applied in an axial or conical direction, for example, relative to the substrate surface. This makes it possible to evaluate the resistance to separation of the adhesive and the substrate under conditions where the load is applied directly along the curvature of the substrate surface, so as to reproduce stresses encountered in real-world applications.

[0018] The thrust force can also be torsional, which involves applying a thrust force with a torsional movement relative to the substrate surface. This makes it possible to evaluate the resistance to separation of the adhesive and the substrate under conditions where a combined torsional and thrust load is applied.

[0019] Current equipment manufacturers offer to perform these adhesion tests following the application of a pushing force, but these are not performed directly. on the actual components of the vehicles. In other words, these tests have drawbacks compared to the reality of the conditions encountered by stabilizer bar bearings on a vehicle in operation.

[0020] More specifically, in these tests, a metal plate is often coated with epoxy to simulate the metallic surface of the substrate. The sample is then prepared by applying the adhesive to the metal surface and attaching the elastomeric material to it, thus roughly mimicking the configuration of the elastic bushing and stabilizer bar. A compression device is then used to exert uniform pressure on the sample. After this preparation phase, the actual test consists of applying a pushing force to the sample to measure the adhesive's resistance to this force. The test results can vary, ranging from complete failure of the elastomer's cohesion to partial adhesion with cohesion failure or complete failure of adhesion. Thus, the sample configuration does not reproduce the actual stresses encountered by stabilizer bar bearings in a driving environment.Indeed, the forces and vibrations experienced by the components of a moving vehicle can be far more complex and dynamic than what is simulated in the laboratory. Thus, although this adhesion test under a force applied by pushing offers a standardized method for evaluating the adhesive's resistance, it has limitations compared to the reality of a vehicle's operating conditions.

[0021] Other equipment manufacturers therefore prefer to perform these adhesion tests directly on the actual components, but these tests involve destructive methods. This means that the components being tested are damaged or destroyed during the process. This makes it impossible to reuse the components for further testing or for actual use in a vehicle, consequently resulting in a waste of materials, resources, and cost.

[0022] It is therefore crucial to be able to guarantee the reliability and reproducibility of adhesion tests under a force applied by thrust when evaluating vehicle suspension components. There is thus a need to implement an automated test, respecting the objectives established by the ASTM D429 test, while avoiding destructive methods, and thereby overcoming the aforementioned drawbacks. Description of the invention

[0023] The present description relates to a bearing sample comprising a component made of a metallic or composite material and having a cavity extending along its entire length, the bearing sample comprising an elastomeric layer intended to receive at least partially said component so as to form a contact interface. The bearing sample is characterized in that the organ is divided from one end to the other along a predetermined axis, forming two distinct parts.

[0024] The bearing sample corresponds to a prototype of an assembly comprising a component surrounded by a bearing, used here for analysis and testing purposes in the context of improving the components of a bearing / component assembly intended to be operational thereafter. More specifically, the bearing sample is designed to simulate various load and motion conditions that a bearing may encounter in real-world applications. Of course, the term "bearing sample" may have different names known to those skilled in the art, as long as the sample as defined by the invention has the same characteristics. For example, a commonly used term to designate the bearing sample is bearing / component prototype.

[0025] The bearing sample, as defined herein, therefore comprises a component having a cavity extending along its entire length and made of either metallic or composite material. The component is associated with an elastomeric layer. The metallic or composite component is thus intended to be in contact with the elastomeric layer in order to form a contact interface.

[0026] The organ is here separated into two parts along a predetermined axis. This division or separation of the organ creates two distinct parts that can be considered as halves or separate sections of the whole organ. This then implies that each part of the organ contains a portion of the organ cavity.

[0027] Such a configuration of the component allows the bearing sample to interact advantageously with the machine intended to apply a load to it. More specifically, when this bearing sample interacts with said machine, the application of the load will occur without excessive friction. To this end, the separation of the component into two distinct parts forms a slot designed to cooperate with the machine, thus allowing a smooth and progressive separation of the elastomer layer from the component.

[0028] According to some embodiments, the predetermined axis is axial, radial or conical with respect to the length of the organ.

[0029] The division of the organ into two distinct parts can then be carried out according to three main orientations relative to the length of the organ. When the axis of separation is axial, this means that the two parts of the organ are separated lengthwise, that is, parallel to its central axis. If the axis of separation is radial, this implies that the two parts of the organ are separated in a direction perpendicular to its central axis, that is, in a plane that intersects the organ radially. Finally, when the axis of separation is conical, this means that the two parts of the organ are separated at an oblique angle to its central axis, thus forming a cone-shaped division.

[0030] These different separation axis orientations allow the structure of the bearing sample to be adapted according to the nature of the thrust force that will be applied by the machine.

[0031] According to some embodiments, the contact interface comprises an adhesive contact surface which is bonded by vulcanization or by gluing, the gluing being carried out hot or cold.

[0032] The adhesive contact surface of the bearing sample can be prepared by vulcanization or bonding, methods commonly used in industry to ensure a bond between the elastomer layer and the component. As a reminder, vulcanization is a chemical process in which the elastomer material is treated with vulcanizing agents such as sulfur, as well as heat. Alternatively, bonding can be used to attach the elastomer layer to the component. In the case of hot bonding, a hot-melt adhesive is applied to the adhesive contact surface and then heated to melt the adhesive and allow it to penetrate the pores of the component and the elastomer. Once cooled, the adhesive hardens to form a bond between the two surfaces. Cold bonding, on the other hand, uses solvent-based or resin-based adhesives that polymerize at room temperature to form an adhesive bond.

[0033] According to some embodiments, the organ is made of steel, or of aluminum alloy, or of a hybrid material.

[0034] A hybrid material is defined as a material that combines two or more types of materials to exploit the advantages of each. Similarly, a composite material is defined as a structure consisting of two distinct phases: a matrix phase and a reinforced phase, such as carbon or glass fibers. Thus, while hybrid materials combine different materials to form a single structure, composite materials integrate distinct materials into a matrix to create a reinforced structure with specific properties.

[0035] For example, when the organ is made of composite material, it may comprise layers of glass fibers alternating with layers of carbon fibers, and when the organ is made of hybrid material, it may consist of a basic metallic structure, such as a steel core, which is then wrapped or coated with a fiber-reinforced polymer material.

[0036] The present disclosure further relates to a method for determining the resistance to separation and the percentage of adhesion between a component made of a metallic or composite material and an elastomeric layer of a bearing sample as defined above. The method is characterized in that it comprises the following steps: 1) a step implementing an automated mechanical test, at ambient temperature or at a temperature between 40°C and 120°C, on the bearing sample by progressively applying a force by pushing through a guide designed to be inserted into the organ cavity and to extend along it so as to cooperate with it, and 2) a step of measuring the resistance to separation and the percentage of adhesion between said organ and the elastomer layer as a function of the applied force.

[0037] Step 1) involves applying a controlled thrust force to the bearing sample to simulate the stresses it would be subjected to under real operating conditions. For this purpose, the thrust force is applied through a guide specifically designed for this purpose. This guide is designed to be inserted into the cavity of the bearing sample's component. Once inserted, the guide extends along the component cavity (in two parts), aligning with and cooperating with its longitudinal axis. The objective of this configuration is to allow the thrust force to be applied precisely and in a controlled manner to the bearing sample. The guide thus ensures correct alignment of the applied force with respect to the component's structure.

[0038] To this end, the guide may include a groove that is aligned with the axis of separation of the component into two parts. More specifically, the axis of separation produces a hollow space into which the groove of the guide can be inserted through slats, for example, which help to maintain the separation of the component into two distinct parts and which minimize unwanted friction during the implementation of step 1).

[0039] Once the force has been applied, step 2) corresponds to the measurement of the resistance to separation between the organ and the elastomer layer of the bearing sample, but also corresponds to the measurement of the percentage of adhesion between the organ and the elastomer layer.

[0040] This adhesion percentage characterizes the quality of the adhesion between the elastomer and the organ in the bearing sample. For example, when the adhesion percentage is greater than 90% of the adhered surface (i.e., outside the adhesive-free contact interface), it corresponds to a surface area that remains adhered to 90% of the total adhered contact interface surface. In this case, the rupture occurs primarily within the elastomer, indicating strong adhesion between the elastomer and the organ. The elastomer then ruptures cleanly and uniformly, leaving a thin layer of elastomer on the organ.

[0041] According to another example, when the percentage of adhesion is less than 10% of the adhered surface, the elastomer detaches from the organ, revealing the metallic or composite surface underneath. Traces of paint or glue may also be observed on the metallic or composite surface, indicating detachment of the elastomer without significant adhesion to the organ. This therefore suggests adhesion insufficiency between the elastomer and the organ, which can compromise the performance of the bearing / organ assembly under real-world operating conditions.

[0042] Such a percentage of adhesion can be observed and evaluated during the application of the pushing force or following separation between the elastomer layer and the organ. To quantify the percentage of adhesion, the proportion of the surface area bonded between the elastomer and the organ that maintains a solid bond can be measured. This can be done, for example, by visually comparing the bonded surface area to the total surface area of ​​the sample.

[0043] Of course, a person skilled in the art understands that the term "automatic" refers to a mechanical test that is carried out without direct intervention from a human operator. This ensures consistent and reproducible execution of the test, while allowing the operator to focus on other aspects, such as analyzing the results.

[0044] According to certain embodiments, the thrust force is applied torsionally, conically or axially with respect to a longitudinal axis of the organ.

[0045] When the thrust force is applied torsionally, it creates a twist or rotational movement around the longitudinal axis of the component. If the thrust force is applied conically, this means that it is exerted in an oblique direction relative to the longitudinal axis of the component, thus creating a pressure or load that gradually decreases towards a specific end or part of the bearing sample. Finally, when the thrust force is applied axially, it is exerted parallel to the longitudinal axis of the component.

[0046] According to certain embodiments, the force by push is applied progressively to induce a separation between said organ and the elastomer layer allowing the observation of a fracture face on said contact surface.

[0047] The thrust force can be applied gradually and in a controlled manner to induce separation between the organ and the elastomer layer, while allowing observation of the failure mechanisms at the contact interface between these two materials. This gradual increase in force creates increasing stresses on the contact interface between the elastomer and the organ, ultimately leading to said separation.

[0048] According to certain embodiments, the fracture pattern is identified and / or the percentage of adhesion is determined by running a machine learning algorithm.

[0049] The identification of the fracture surface and the determination of the percentage of adhesion can be carried out using a machine learning algorithm. This algorithm is a computer tool that can analyze data and extract models or information derived from this data without being explicitly programmed to perform a specific task.

[0050] In this context, the machine learning algorithm can be trained from experimental data comprising observations, presented in two dimensions (2D) or three dimensions (3D), acquired by means such as vision cameras or laser profilometers, of fracture surfaces and percentage adhesion measurements under different test conditions. This data may include images or detailed descriptions of the observed fracture modalities, as well as quantitative measurements of the percentage adhesion.

[0051] Once the algorithm has been trained on this data, it can be used to analyze new observations of fracture surfaces and percentage adhesion measurements. The algorithm can then automatically identify the specific characteristics associated with different fracture surfaces, such as the presence of traces of paint or glue, the adhesive fracture surface, etc. Furthermore, as mentioned above, it can also calculate the percentage adhesion based on these characteristics.

[0052] The advantage of using a machine learning algorithm is its ability to identify complex patterns or relationships that can be difficult to detect manually. This allows for an objective analysis of the results of the push force application test, which can contribute to a better understanding of the quality of adhesion between the elastomer and the organ in the bearing sample.

[0053] According to certain embodiments, said component is a vehicle stabilizer bar.

[0054] The present exposition further relates to a computer program comprising instructions executable by a processor, which, when executed by the processor, implement the method of determining a resistance to separation and a percentage of adhesion as defined above.

[0055] The computer program can be coded in any programming language and take the form of source code, object code, or an intermediate form between source code and object code, such as a partially compiled form or any other desired form. Such a program can be stored on a computer-readable data medium.

[0056] The storage medium in question may be an internal or external hard drive, a USB flash drive, a CD-ROM, a memory card, or a cloud storage service. Of course, this list is not exhaustive and may include any other data storage medium known to a person skilled in the art and not mentioned herein.

[0057] The present description further relates to a device for determining the resistance to separation and the percentage of adhesion between a component made of a metallic or composite material and an elastomeric layer of a bearing sample. The device comprises: - application means comprising a guide intended to be inserted into the cavity of the organ and to extend along it so as to cooperate with it, the application means being configured to perform an automatic mechanical test, at ambient temperature or at a temperature between 40°C and 120°C, on the bearing sample by progressively applying a force by pushing through said guide; and - measuring means configured to measure the resistance to separation between said organ and the elastomer layer as a function of the applied force.

[0058] This device is designed to perform tests by applying a controlled thrust force to bearing samples as defined above, thus allowing analysis of their resistance to separation and their percentage of adhesion. In other words, this device is a testing machine that acts on the bearing sample by applying a controlled thrust force via the guide described above, and by measuring the resistance to separation as well as the percentage of adhesion between the component and the elastomer layer.

[0059] Of course, a person skilled in the art understands that the term "automatic" refers to a mechanical test that is carried out without direct intervention from a human operator. This ensures consistent and reproducible execution of the test, while allowing the operator to focus on other aspects, such as analyzing the results.

[0060] According to some embodiments, the device includes computing means configured to identify a fracture face intended to be observed following a progressive application of force by pushing inducing a separation between said organ and the elastomer layer, and / or to determine the percentage of adhesion, by executing a machine learning algorithm.

[0061] The aforementioned features and advantages, as well as others, will become apparent from the following detailed description, examples of embodiments of the vehicle stabilizer bar bearing, and the proposed stabilizer assembly. This detailed description refers to the accompanying drawings.

[0062] The accompanying drawings are schematic and are intended primarily to illustrate the principles of the exposition. On these drawings, from one figure to another, identical elements (or parts of elements) are identified by the same reference symbols. [Fig.1] The [Fig.1] is a perspective view of a stabilizing assembly; [Fig.2] The [Fig.2] is a perspective view of an example of a landing; [Fig.3A], [Fig.3B], [Fig.3C] Figures 3A, 3B and 3C each schematically present an alternative configuration of a bearing sample according to the invention; [Fig.4] Fig.4 schematically illustrates a method for determining a resistance to separation and a percentage of adhesion between two components of such a bearing sample according to an embodiment of the invention; [Fig.5] Fig.5 schematically illustrates a device for determining the resistance to separation and the percentage of adhesion between these two components according to an embodiment of the invention; [Fig. 6A], [Fig. 6B], [Fig. 6C] Figures 6A, 6B and 6C each schematically illustrate an example of means of applying said device according to an embodiment of the invention; and [Fig.7] Fig.7 schematically illustrates an example of a fracture face observed following the implementation of said application means according to an embodiment of the invention.

[0063] Description of embodiments and implementation methods

[0064] To make the invention more concrete, a bearing sample is described in detail below, with reference to the accompanying drawings. It should be noted that the invention is not limited to this example.

[0065] As indicated above, the bearing sample corresponds to a prototype of an assembly comprising a metallic or composite component surrounded by a bearing. By way of example, the bearing in question may be designed for a stabilizer assembly 1 for a vehicle, for example, as illustrated in [Fig. 1]. Of course, the vehicle is understood to mean any mobile structure, preferably an automobile such as a truck, car, or utility vehicle, designed for the transport of persons or goods.

[0066] Such a stabilizer assembly 1 is illustrated in [Fig. 1] solely by way of a non-limiting example of the application of the bearing sample. More specifically, the stabilizer assembly 1 comprises a stabilizer bar 10, solid or hollow, painted or unpainted, the central part of which 11 is equipped with two bearings 20. Such bearings 20 are intended to be fixed to the vehicle chassis, while the ends 12 of the stabilizer bar 10 are intended to be fixed to parts of the vehicle integral with each wheel of the same axle, in particular the suspension triangle of each wheel of the axle.

[0067] The bearings 20 can be solid or in the form of two split bearings intended to be assembled together. More specifically, a solid bearing is characterized by a unitary mechanical structure without significant slots, openings, or discontinuities in its structure, whereas a split bearing (or half-bearing) has a structure mechanical part with an opening or slot, allowing it to be installed around the chassis and assembled with another slotted bearing or to be removed from around the chassis.

[0068] By way of example, when the bearing 20 is solid, it can completely enclose the stabilizer bar 10 along an axis A corresponding to the direction of extension of the stabilizer bar 10 when the bearing 20 is mounted. Conversely, when the bearing 20 is split, it can only enclose the stabilizer bar 10 on one side of the axis A, while another split bearing 20 encloses the stabilizer bar 10 on the other side of the axis B.

[0069] In this example, the bearing 20 is solid and has a general U-shaped form, but alternatively, it may be cylindrical, conical, or elliptical. Since the flange portion 30 can also conform to the shape of the bearing 20, its cavity can be cylindrical, conical, or elliptical so as to completely surround the stabilizer bar 10.

[0070] In this case, the flange portion 30 corresponds to a flange 30. Conversely, the flange portion 30 can be semi-cylindrical, semi-conical, or semi-elliptical in shape when the bearing 20 is split and thus partially surrounds the stabilizer bar 10. In this latter case, the flange portion 30 comprises first and second flange elements 30 configured to be joined against each other. Each flange element 30 then includes a cavity portion, each lined with the elastomeric coating 60 or elastomeric layer 60, together forming said cavity of the flange portion 30.

[0071] It should be noted that the elastomer layer 60 of the bearing 20 intended to be in direct contact with the stabilizer bar 10 may have a cylindrical shape.

[0072] In the following description and for the sake of brevity, a "bearing" represents either a solid bearing or a split bearing. In other words, the tests performed on the bearing sample may lead to the final production of either a solid bearing or a split bearing.

[0073] Different configurations of the bearing sample are illustrated respectively in Figures 3A, 3B and 3C under reference numeral 70. Such a bearing sample 70 represents an important component for evaluating the bond between metallic or composite materials and an elastomeric layer. More specifically, this bearing sample comprises a component 71 which may correspond to a prototype of at least a portion of the stabilizer bar 10, and may be made of steel, aluminum alloy, or a hybrid material that combines two or more types of materials to exploit the advantages of each.

[0074] Furthermore, the tier 70 sample is provided with an elastomer layer 72 corresponding to the prototype of the elastomer layer 60 of tier 20. This elastomer layer 72, while like that of bearing 20, is arranged so as to receive at least partially the component 71, thus forming a contact interface 73.

[0075] The contact interface 73 has an adhesive contact surface 74 over its entire surface which can be connected to the component 71 by vulcanization or by bonding, whether carried out hot or cold.

[0076] Thus, the bearing sample 70 represents a specific assembly designed to evaluate the adhesion between the metallic or composite material component and the elastomer layer. By combining the properties of these two components, this sample offers a faithful representation of the conditions encountered in the final configuration of the stabilizer bar 10, thereby enabling precise and realistic tests to be carried out on the quality of the adhesion.

[0077] According to a first configuration of the bearing sample 70 illustrated in [Fig. 3A], the component 71 is divided radially from one end to the other, thus forming two distinct parts PI and P2. The separation axis 101 is therefore radial and along a cutting plane perpendicular to the axis A.

[0078] According to a second configuration of the bearing sample 70 illustrated in [Fig. 3B], the component 71 is divided axially from one end to the other, thus also forming two distinct parts PI and P2. The separation axis 101 is therefore axial here and along a cutting plane so as to separate the two parts PI and P2 along its length, i.e. parallel to the axis A.

[0079] According to a third configuration of the bearing sample 70 illustrated in [Fig. 3C], the separation axis 101 is this time conical. This means that the two parts PI and P2 of the component 71 are separated along an oblique orientation with respect to its axis A, thus forming a cone-shaped division.

[0080] The step sample 70, according to the first configuration, the second configuration or the third configuration, is used to implement a method 80 for determining a resistance to separation and a percentage of adhesion between the organ 71 and the elastomer layer 72 of the step sample 70.

[0081] More specifically, this percentage of adhesion characterizes the quality of the adhesion between the elastomer 72 and the component 71 in the bearing sample 70. For example, when the percentage of adhesion is greater than 90% of the adhered surface, it corresponds to a surface that remains adhered to 90% of the total initially adhered surface of the contact interface 73. In this case, the break occurs mainly within the elastomer 72, which indicates strong adhesion between the elastomer 72 and the component 71. The elastomer 72 then breaks cleanly and uniformly with a thin layer of elastomer 72 remaining on the component 71.

[0082] According to another example, when the percentage of adhesion is less than 10% of the adhered surface, the elastomer 72 detaches from the organ 71, revealing the surface metallic or composite material underneath. Traces of paint or glue may also be observed on the metallic or composite surface, indicating detachment of the elastomer 72 without significant adhesion to the component 71. This therefore suggests insufficient adhesion between the elastomer 72 and the component 71, which may compromise the performance of the bearing / component assembly under real operating conditions.

[0083] To this end, [Fig.4] presents a flowchart describing the different steps of said process of 80.

[0084] The process 80 begins with a step El implementing a mechanical, automatic and repeatable test on the bearing sample 70 by progressively applying a force by pushing through a guide intended to be inserted into the cavity of the organ 71 and to extend along it so as to cooperate with it.

[0085] Such a guide is illustrated in Figures 6A, 6B, and 6C. This guide is designed to be inserted into the cavity of the bearing sample organ. Once inserted, the guide extends along the cavity of the organ 71 (in two parts P1 and P2), aligning with and cooperating with its longitudinal axis A. The purpose of this configuration is to allow the thrust force to be applied precisely and in a controlled manner to the bearing sample 70. The guide thus ensures correct alignment of the force with respect to the organ structure. The various configurations of the guide will be explained by way of example below.

[0086] The thrust force can optionally be applied gradually and in a controlled manner, for example at a speed of 10 mm / min (or millimeters per minute), in order to induce separation between the component 71 and the elastomer layer 72, while allowing observation of a fracture surface at the contact interface 73 between these two components. Such observation can be presented in two dimensions (2D) or three dimensions (3D) and can be acquired by means such as vision cameras or laser profilometers.

[0087] The process 80 continues with the implementation of a step E2 for measuring the resistance to separation and the percentage of adhesion between said component 71 and the elastomer layer 72 as a function of the applied force (push force). The percentage of adhesion can then be observed and evaluated. To quantify the percentage of adhesion, the proportion of the surface area bonded between the elastomer 72 and component 71 that maintains a solid bond can be measured. This can be done, for example, by visually comparing the bonded surface area to the total surface area of ​​the sample.

[0088] However, it is possible to identify the fracture surface and also to determine the percentage of adhesion using other techniques. To this end, process 80 optionally includes a step E3 for identifying the fracture surface and / or determining the percentage of adhesion by running a machine learning algorithm. For example, the machine learning algorithm can be trained on experimental data including observations of fracture surfaces and measurements of percentage of adhesion under different test conditions. This data can include images or detailed descriptions of the observed fracture modalities, as well as quantitative measurements of the percentage of adhesion.

[0089] Once the algorithm has been trained on this data, it can be used to analyze new observations of fracture surfaces and percentage adhesion measurements. The algorithm can then automatically identify the specific characteristics associated with different fracture surfaces, such as the presence of traces of paint or glue, the adhesive fracture surface, etc. Furthermore, as indicated, it can also calculate the percentage adhesion based on these characteristics. These new observations and analyses performed by the algorithm can be automatically integrated into a database to which the algorithm is connected, thereby increasing the reliability of its future analyses.

[0090] The advantage of using a machine learning algorithm is its ability to identify complex patterns or relationships that can be difficult to detect manually. This allows for an objective analysis of the results of the force-push test, which can contribute to a better understanding of the quality of adhesion between the elastomer and the organ in the bearing sample.

[0091] Figure 5 illustrates a device 90 for determining the resistance to separation and the percentage of adhesion between the component 71 and the elastomer layer 72 of the bearing sample 70. More specifically, this device 90 is designed to perform controlled thrust force application tests on bearing samples 70, thus enabling the analysis of their resistance to separation and their percentage of adhesion. This device allows the implementation of the process 80.

[0092] For this purpose, the device 90 includes application means 91 configured to implement an automatic mechanical test on the sample 70 by progressively applying a force by pushing through said guide which is a component of the application means 91.

[0093] The device 90 further includes measuring means 92 configured to measure the resistance to separation and the percentage of adhesion between said organ 71 and the elastomer layer 72 as a function of the applied force (push force).

[0094] Finally, the device 90 may include computing means 93 configured to identify a fracture surface intended to be observed following a progressive application of force by thrust inducing a separation between said component 71 and the layer elastomer 72, and / or determine the percentage of adhesion, by an execution of said machine learning algorithm.

[0095] Of course, the calculation means 93 and the measurement means 92 can be implemented by various technical means well known to those skilled in the art. As for the application means 91, three different configurations of the guide are illustrated respectively in Figures 6A, 6B and 6C, so as to cooperate with the component 71.

[0096] As indicated above, in each of the three illustrated guide configurations, the sample 70 is subjected to a force applied by pushing.

[0097] For example, as illustrated in [Fig. 6A], the guide 200 is designed so that the thrust force is applied torsionally 202 or axially 201 via the guide 200, relative to the longitudinal axis A of the member 71 of the bearing specimen. The guide 200 is here designed to cooperate with the member 71 when the two separate parts P2 and PI are divided along a radial axis as illustrated in [Fig. 3A].

[0098] Furthermore, as illustrated in [Fig.6B], the guide 200 is designed so that the thrust force is applied axially 201 when the two separate parts PI and P2 of the member 71 are divided along the axial axis as illustrated in [Fig.3B].

[0099] Finally, as illustrated in [Fig.6C], the guide 200 is designed so that the thrust force is applied conically 203 when the two separate parts P2 and PI of the member 71 are divided along an oblique axis as illustrated in [Fig.3C].

[0100] In order for the guide 200 to cooperate with the member 71, the guide 200 is provided here with a groove aligned with the separation axis 101 of the member so as to apply the force by pushing without excessive friction and to ensure delicate and precise handling of the bearing sample 70. For this purpose, the guide 200 may include small slats intended to fit into the space located at the separation axis, but obviously, a person skilled in the art is able to select other configurations of the guide 200 so as to make it cooperate with the space created by the separation axis 101.

[0101] The thrust force can be applied progressively by the application means 91 on the bearing sample 70 to induce a separation between said organ 71 and the elastomer layer 72 allowing the observation of a fracture face on said contact interface 73.

[0102] Such a fracture surface is illustrated in [Fig. 7]. More specifically, in this example, the contact interface 73 is fully adhesive following the application of an adhesive. The contact interface 73 has residues 77 of elastomer 72 in a first zone Z1 and in a second zone Z2 of the contact interface 73. The fracture occurs here primarily within the elastomer, indicating strong adhesion between the elastomer 72 and the component 71. The elastomer 72 then breaks. neatly and uniformly with a thin layer of elastomer (residue) 77 remaining on organ 71.

[0103] The contact interface 73 further comprises a third zone Z3 free of elastomer residue 72, indicating detachment of the elastomer without significant adhesion to the component 71. Thus, the elastomer 72 has completely detached from the component 71, thereby revealing the metallic or composite surface beneath. Traces of paint or glue can also be observed on the metallic or composite surface. This therefore suggests insufficient adhesion between the elastomer 72 and the component 71.

[0104] Although the present invention has been described with reference to specific embodiments, it is evident that modifications and changes can be made to these examples without departing from the general scope of the invention as defined by the claims. In particular, individual features of the various embodiments illustrated / mentioned can be combined in additional embodiments. For example, when a bearing as the final product is of the split type, a person skilled in the art can perform the test sequentially on the bearing sample adapted for this purpose (in other words, on split-type bearing samples) without departing from the scope of the invention. Therefore, the description and drawings should be considered in an illustrative rather than a restrictive sense.

[0105] It is also evident that all the characteristics described with reference to a process are transposable, alone or in combination, to a device, and conversely, all the characteristics described with reference to a device are transposable, alone or in combination, to a process.

Claims

Demands

1. Bearing sample (70) comprising a member (71) made of a metallic material or of a composite material and having a cavity extending over its entire length, the bearing sample (70) comprising an elastomeric layer (72) intended to receive at least partially said member (71) so as to form a contact interface (73), the bearing sample (70) being characterized in that the member (71) is divided from one end to the other along a predetermined axis, forming two distinct parts (PI, P2).

2. Bearing sample (70) according to claim 1, wherein the predetermined axis is axial, radial or conical with respect to the length of the member (71).

3. Bearing sample (70) according to claim 1 or 2, wherein the contact interface (73) comprises an adhesive contact surface (74) which is bonded by vulcanization or by gluing, the gluing being carried out hot or cold.

4. Bearing sample (70) according to any one of the preceding claims, wherein the component (71) is made of steel, or of aluminum alloy, or of a hybrid material.

5. A method (80) for determining the resistance to separation and the percentage of adhesion between a component (71) made of a metallic material or a composite material, and an elastomeric layer (72) of a bearing sample (70) according to any one of claims 1 to 4, the method (80) being characterized in that it comprises the following steps: 1) a step (E1) implementing an automatic mechanical test, at ambient temperature or at a temperature between 40°C and 120°C, on the bearing sample (70) by progressively applying a force by pushing through a guide intended to be inserted into the cavity of the component (71) and to extend along it so as to cooperate with it, and 2) a step (E2) for measuring the resistance to separation and the percentage of adhesion between said component (71) and the elastomeric layer (72) as a function of the force applied.

6. Method (80) according to claim 5, wherein the thrust force is applied torsionally, conically or axially with respect to a longitudinal axis of the member (71).

7. Method (80) according to claim 5 or 6, wherein the push force is applied progressively to induce a separation between said member (71) and the elastomer layer (72) allowing the observation of a fracture face on said contact surface (73).

8. Method (80) according to claim 7, wherein the fracture face is identified and / or the percentage of adhesion is determined by an execution of a machine learning algorithm.

9. Method (80) according to any one of claims 5 and 8, wherein the component (71) is a vehicle stabilizer bar (10).

10. A computer program comprising instructions executable by a processor, which, when executed by the processor, implement the method for determining a resistance to separation and a percentage of adhesion according to any one of claims 5 to 9.

11. Device (90) for determining a resistance to separation and a percentage of adhesion between a component (71) made of a metallic material or of a composite material, and an elastomer layer (72) of a bearing sample (70) according to any one of claims 1 to 4, the device (90) comprising: - application means (91) comprising a guide intended to be inserted into the cavity of the component (71) and to extend along it so as to cooperate with it, the application means (91) being configured to carry out an automatic mechanical test, at ambient temperature or at a temperature between 40°C and 120°C, on the bearing sample (70) by a progressive application of a force by pushing through said guide; and - measuring means (92) configured to measure the resistance to separation between said organ (71) and the elastomer layer (72) as a function of the applied force.

12. Device (90) according to claim 11, comprising computing means (93) configured to identify a fracture face intended to be observed following a progressive application of force by pushing inducing a separation between said member (71) and the elastomer layer (72), and / or determine the percentage of adhesion, by executing a machine learning algorithm.

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