Friction machine for testing tribological performance of material under multiple working conditions and test method

Abstract

The invention discloses a friction machine for testing the tribological performance of a material under multiple working conditions and a test method. The friction machine comprises a test bed, a friction plate and a friction plate, the first friction mechanism comprises a first friction piece, a friction piece position regulator for accommodating and fixing the first friction piece, and a lifting driving mechanism; the second friction mechanism comprises a second friction piece and a rotary driving mechanism; the load applying mechanism is arranged on the test bed and is used for applying a load to the first friction piece through the friction piece position regulator so as to enable the first friction piece and the second friction piece to keep surface contact in the test process; and the detection mechanism is arranged on the test bed and comprises a controller and a friction force detection unit connected with the controller, and the controller calculates tribological parameters under multiple working conditions according to load data detected by the friction force detection unit. The device has the beneficial effects that the friction performance of the composite material under the dry friction condition and the lubricating friction condition can be tested, the test is convenient, and the result is accurate.

Description

Technical Field

[0001] The present application belongs to the field of wear testing, and specifically relates to a friction machine and a test method for testing the tribological properties of materials under multiple working conditions. Background Art

[0002] Tribology is one of the most important disciplines in contemporary engineering science. The performance of a new material, especially when the working environment is relatively harsh, requires not only the traditional mechanical, physical and chemical test assessments, but also the performance test of friction and wear. At present, there are many kinds of friction and wear testers with ball-disc structure or column-disc structure, but most of them cannot study their characteristics in the wide range of stable changes in the speed-force parameters of friction interaction under dry friction conditions (without lubricant) and under the conditions of using lubricants. For example, Patent 1: G01N 19 / 02 (2006.01) of Khmelnitsky State University, a friction coefficient tribometer, which determines the friction coefficient by measuring the rotation angle of the device installed on the cylinder, and rotates by the torque generated by the contact friction force. Its load is generated by the mass of the device and the attached suspended object. The tribometer has a reinforcing ring and two radially movable centering elements. However, the disadvantage of the device is that it is difficult to determine the wear condition based on the geometric parameters of the sample, which reduces the efficiency of using the device for tribological testing, and the device cannot be tested in the mode of using lubricants. Comparative Patent 2: G01N 19 / 02, G01N 3 / 56 (2006.01) of Azov State Technical University, a tribometer for testing the wear of materials. The tribometer comprises a housing, an element mounted on a rotating shaft, a moving mechanism, a disc-shaped comparison sample mounted on a spindle, and a friction control element. The housing is provided with a bushing, in which there is a fixing screw that interacts with the sample. The rotating shaft has a gap and can impact in planes parallel and perpendicular to it, and the moving mechanism with an adjustable pressing force between the housing with the sample and the disc-shaped comparison sample mounted on the spindle with the gap made in the form of a spring can move along the axis and rely on an adjusting screw mounted on a flange, which is mounted on the spindle and connected to the comparison sample by a wire. The disadvantage of the device is the lack of the ability to self-install and adjust the protrusion of the sample, which significantly reduces the ability to study the test process of the wear resistance of the sample. Comparative Patent 3: IPC G01N3 / 56 (2006.01) of Yury Ivanivna Antoshkina (UA), a friction machine for ensuring the characterization of solid friction interactions, the friction machine having a housing, a moving rod with a bracket, a sample and a comparison sample, a rotary drive, a vertical forced vibration exciter, a load system, and a system for measuring the main parameters. The contact between the sample holder of the device and the sample itself is designed so that the sample and the sample holder have a certain relative freedom of movement. In order to reduce the friction in the contact area, it is considered to be coated with a friction-reducing material or a layer of lubricant. The sample is rigidly connected to the exciter in the horizontal direction. The exciter is connected to the housing of the friction machine. The exciter can induce horizontal vibrations relative to the contact between the sample and the comparison sample.The ability to study the interaction characteristics of solids under the influence of tribological systems subjected to horizontal forced vibrations can be achieved. The disadvantage of the device is that the friction machine does not allow research when using lubricants. Comparative Patent 4: As Soviet Union No. 1619398A1 friction machine of the Ternopil Branch of Lviv Polytechnic Institute is closest to the present invention in terms of technical essence and implementation results. The device housing, a disc-shaped sample mounted thereon, a rotary drive, a sample support, a load component and a friction torque meter. In order to improve the accuracy of tribological property research by reducing the dynamic load on the test sample and expanding its load range during fluctuations in the friction coefficient, the machine is equipped with a locking position sample support guide element, which is intended to mount the support on which the sample is mounted. The latter (sample) has the ability to move radially relative to the disc-type comparison sample. The sample support has the ability to oscillate the shaft, the axis of which is parallel to the plane of the disc-type comparison sample and perpendicular to the longitudinal guide axis. The sample support has the ability to oscillate the shaft, the axis of which is parallel to the plane of the disc-type comparison sample and perpendicular to the longitudinal guide axis. The guide axis is hingedly connected to the shaft at one end and to the load element at the other end. The axis of the cylindrical hinge is perpendicular to the plane of the sample disc. The longitudinal axis of the sample holder guide element and the axis of the sample holder are located in the same plane, which is perpendicular to the plane of the disc-shaped comparison specimen. The disadvantage of this friction machine is that it is not possible to test the friction pair when the lubricant is supplied to the friction contact area during the study of lubricants in various lubrication modes and load speed working conditions of the friction pair. At the same time, there is no system for centering the specimen in the direction of the load axis, which reduces the accuracy of the tribological properties test.

[0003] Therefore, there is an urgent need for a friction machine that can study the characteristics of composite materials under dry friction conditions (without lubricant) and lubricated friction conditions (with lubricant) in a wide range of smooth changes in the speed-force parameters of friction interaction. Summary of the invention

[0004] In view of the shortcomings of the prior art mentioned above, the purpose of the present application is to provide a friction machine and test method for testing the tribological properties of materials under multiple working conditions, so as to solve the current problems of being unable to study the friction properties of composite materials under both dry friction conditions and lubricated friction conditions, small test range and low data accuracy.

[0005] To solve the above problems, the technical solution adopted in this application is:

[0006] The friction machine for testing the multi-condition tribological performance of materials described in the present invention is characterized by comprising:

[0007] Test bench;

[0008] The first friction mechanism comprises a first friction member, a friction member position regulator for accommodating and fixing the first friction member, and a lifting drive mechanism disposed on the test bench for driving the friction member position regulator to lift;

[0009] The second friction mechanism comprises a second friction member and a rotation driving mechanism disposed on the test bench for carrying and driving the second friction member to rotate horizontally;

[0010] a load applying mechanism, disposed on the test bench, for applying a load to the first friction member through a friction member position regulator so that the first friction member and the second friction member maintain surface contact during the test; and / or

[0011] The detection mechanism is arranged on the test bench and comprises a controller and a friction detection unit connected to the controller. The controller calculates the tribological parameters of the friction pair under multiple working conditions according to the load data detected by the friction detection unit.

[0012] As a preferred embodiment of the present application, the friction member position regulator includes a sample support rack guiding element, a sample fixing assembly and an oil tank, wherein the sample support rack guiding element is connected to the lifting drive mechanism and is used to drive the sample fixing assembly to lift and lower; the sample fixing assembly is adjustably arranged in the sample support rack guiding element, a sample cavity for allowing the first friction member to enter and exit is provided at the lower part of the sample fixing assembly, a liquid storage cavity is provided between the top of the sample fixing assembly and the sample support rack guiding element, and the liquid storage cavity is connected to the sample cavity and the oil tank.

[0013] As a preferred embodiment of the present application, the sample support rack guiding element is a U-shaped structure with its opening facing the test bench below.

[0014] As a preferred embodiment of the present application, horizontal through grooves are symmetrically provided on two opposite side walls of the sample support rack guiding element.

[0015] As a preferred embodiment of the present application, a liquid adding hole communicating with the liquid storage cavity is provided on the top of the sample support guide element.

[0016] As a preferred embodiment of the present application, the liquid adding hole is a tapered hole that is larger at the top and smaller at the bottom.

[0017] As a preferred embodiment of the present application, the sample fixing assembly includes a sample support rack, a tightening sleeve, a cover and a buffer member, the sample support rack is adjustably installed in the sample support rack guide element, the end surface of the sample support rack away from the test bench is provided with a recess, and the recess and the inner surface of the sample support rack guide element together define a liquid storage cavity; the tightening sleeve and the cover are coaxially installed in the sample support rack, and together define a sample cavity with a bottom end open for the first friction member to enter and exit; the buffer member is connected to the inner surface of the cover facing the workbench, and is used to prevent the first friction member from directly contacting the cover.

[0018] As a preferred embodiment of the present application, the center of the recess protrudes toward a side away from the test bench to form a convex seat, and the end face of the convex seat away from the test bench is processed with a first arc groove; the inner surface of the sample support guide element facing the test bench is processed with a second arc groove, the first arc groove and the second arc groove are arranged opposite to each other up and down, and a spherical support member is sandwiched between the two.

[0019] As a preferred embodiment of the present application, the diameter of the spherical support member is smaller than the diameters of the first circular arc groove and the second circular arc groove.

[0020] As a preferred embodiment of the present application, a working chamber is defined between the sample support frame and the sealing cover, and a plurality of grooves are processed on the inner wall of the fixing sleeve. The working chamber is connected with the liquid storage chamber and the grooves, and is used to fill the lubricant in the liquid storage chamber into the contact area between the first friction member and the second friction member, thereby lubricating the contact area.

[0021] As a preferred embodiment of the present application, a connecting hole is provided inside the sample support frame, one end of the connecting hole is connected to the oil storage cavity, and the other end of the connecting hole is connected to the working cavity.

[0022] As a preferred embodiment of the present application, the groove is a V-shaped through groove extending along the central axis of the adapter sleeve, and the notch of the V-shaped through groove faces the central axis of the adapter sleeve.

[0023] As a preferred embodiment of the present application, the buffer member is a spring, one end of which is connected to the cover, and the other end of which abuts against the end surface of the first friction member movably inserted in the sample cavity and away from the test bench, so as to ensure that the end surface of the first friction member close to the test bench is always in contact with and pressed against the second friction member during the test.

[0024] As a preferred embodiment of the present application, the rotary drive mechanism includes a hydraulic motor, the hydraulic motor is installed on the test bench, and the output shaft of the hydraulic motor is equipped with a storage cup with an open top for accommodating the second friction member.

[0025] As a preference of the present application, the first friction member is a cylindrical friction member movably inserted into the sample cavity.

[0026] As a preferred embodiment of the present application, the outer diameter of the first friction member is slightly smaller than the inner diameter of the sample cavity, so as to ensure that the first friction member can freely enter and exit the sample cavity along the axis of the sample cavity, thereby reducing the dynamic load during the tribological test of the anti-friction material and lubricant mixture.

[0027] As a preference of the present application, the second friction member is a disc-type friction member, and the surface of the second friction member away from the test bench is a horizontal friction surface.

[0028] As a preferred embodiment of the present application, the load application unit includes a bracket, a power load rod, a weight and a counterweight block. The power load rod is pivotally connected to the bracket through a pivot shaft, the short arm end of the power load rod is equipped with a counterweight block, and the long arm end of the power load rod is hung with a weight plate through a suspension rod. The weight is placed in the weight plate for adjusting the load applied between the first friction mechanism and the second friction mechanism.

[0029] As a preferred embodiment of the present application, the friction force detection unit includes a strain gauge, a tension beam, a force transmission rod and a bearing. The other end of the force transmission rod is connected to the test end of the strain gauge through the tension beam. A bearing is installed at one end of the force transmission rod. The bearing is located directly below the dynamic load rod. The bearing is rotatably installed on the top of the sample support guide element to transmit the pressure applied by the dynamic load rod to the strain gauge via the force transmission rod.

[0030] As a preference of the present application, the detection mechanism further includes a resistance detection unit for detecting the contact resistance between the first friction member and the second friction member.

[0031] The present invention also provides a test method using the friction machine for testing the tribological properties of materials and lubricants, characterized in that it comprises the steps of:

[0032] Determine the size of the friction surfaces of the first friction member and the second friction member based on the materials, specified precision and quality parameters of the first friction member and the second friction member, and cut the materials into the first friction member and the second friction member;

[0033] Place the first friction member in the sample cavity, place the second friction member in the placement cup and fix it to the placement cup, and add a proper amount of lubricant into the oil tank;

[0034] Adjusting the position of the first friction member so that the first friction member contacts the second friction member at a set position;

[0035] The working state of the friction machine is adjusted according to the test conditions, the load required for the test is applied by the load applying mechanism, the rotary drive mechanism sets the test speed and then drives the second friction member to rotate horizontally to perform the friction test, the friction force detection unit obtains the load data applied between the first friction member and the second friction member, the rotary drive mechanism obtains the real-time rotation speed of the second friction member, and the controller calculates the tribological parameters of the friction pair under various working conditions; the tribological parameters at least include friction force.

[0036] The test conditions include at least dry friction conditions (i.e., the contact area is in a state without lubricant) and lubricated conditions (i.e., the contact area is in a state with lubricant), wherein the test under lubricated conditions includes the steps of: introducing lubricant into the contact area between the first friction member and the second friction member.

[0037] Compared with the prior art, the beneficial effects of this application are:

[0038] 1. The friction machine of the present invention can be used to study materials in boundary lubrication mode and determine tribological properties during friction and wear, that is, to study the tribological properties of friction pairs in a wide range of stable changes in the speed-force parameters of friction interaction under dry friction conditions (without lubricant) and lubricated friction conditions (with lubricant) of composite materials;

[0039] 2. The present invention reduces the influence of dynamic load on the test sample (including the transition process from dry friction to lubricated friction) through the active cooperation between the adapter sleeve and the first friction member, and significantly improves the efficiency and reliability of tribological research results;

[0040] 3. It has a wide range of application environments. The equipment can be used not only in laboratories but also in production conditions. The friction member of the present invention expands the test range of the load force parameters applied to the friction pair, and ensures a high load value through the arm ratio on the dynamic load rod and the guide element of the sample support frame. The sensitivity and stability of the force parameter change can be guaranteed during the entire test process. The sliding speed is 0.2-12 m / s, and the specific load is 0.15-40 MPa.

[0041] 4. Cylindrical test samples of different sizes can be used: diameter of 2 to 11.2 mm, height of 0.1 to 25 mm, and anti-contrast samples of 100 to 250 mm in diameter and 7 mm in thickness;

[0042] 5. The first friction member and the second friction member are simple to manufacture, and further metallographic tests are performed on their structural states;

[0043] 6. Convenient to observe and monitor the friction and wear process of the contact area;

[0044] 7. The overall rigidity of the friction machine is high, which can significantly reduce vibration and noise, especially the vibration and noise of the first friction mechanism, the second friction mechanism and the load application mechanism, ensuring objective data when studying the friction and wear process;

[0045] 8. By using springs and spherical supports in the sample fixing assembly, the positioning accuracy of the friction pair in the running-in state and normal friction and wear state is ensured;

[0046] 9. The present invention can use the entire friction surface of the second friction member, thereby improving the utilization rate of the friction member. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a test flow chart of the present invention.

[0048] Figure 2shows an overall axonometric view of a friction machine used to test the tribological properties of materials and lubricants;

[0049] Figure 3 A top view of the friction machine is shown;

[0050] Figure 4 Shows Figure 3 AA section to better show the structure;

[0051] Figure 5 for Figure 4 The enlarged view of point E shows the installation schematic diagram of the friction member position regulator and the first friction member;

[0052] Figure 6 It shows Figure 5 BB profile;

[0053] Figure 7 Shows Figure 5 GG profile;

[0054] Figure 8 Shows Figure 5 F-direction view;

[0055] Fig. 9 Shows Figure 8 HH profile.

[0056] Fig.10 It is a force diagram of the dynamic load rod of the present invention. Description of the drawings:

[0058] 1. Test bench;

[0059] 2. First friction mechanism; 21. First friction member; 22. Friction member position regulator; 23. Lifting drive mechanism;

[0060] 221, sample support guide element; 222, sample fixing assembly; 223, liquid storage chamber; 224, spherical support member; 225, working chamber; 228, oil tank; 2211, horizontal through groove; 2212, liquid adding hole; 2213, second arc groove; 2214, first connecting seat; 2215, second connecting seat; 2220, convex seat; 2221, sample support; 2222, adapter sleeve; 2223, cover; 2224, buffer member; 2225, first arc groove; 2226, groove; 2227, connecting hole;

[0061] 3. Second friction mechanism; 31. Second friction member; 32. Rotation drive mechanism; 321. Hydraulic motor; 322. Storage cup; 323. Locking screw;

[0062] 4. Load applying mechanism; 41. Bracket; 42. Power load rod; 43. Weight; 44. Counterweight;

[0063] 5. Detection mechanism; 51. Friction force detection unit; 511. Strain gauge; 512. Tension beam; 513. Force transmission rod; 514. Bearing. DETAILED DESCRIPTION

[0064] The following describes the implementation of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application.

[0065] It should be noted that the process equipment or devices not specifically specified in the following embodiments are all conventional equipment or devices in the art.

[0066] In addition, it should be understood that one or more method steps mentioned in this application do not exclude the existence of other method steps before or after the combination step or the insertion of other method steps between these explicitly mentioned steps, unless otherwise specified; it should also be understood that the combination connection relationship between one or more devices / apparatuses mentioned in this application does not exclude the existence of other devices / apparatuses before or after the combination device / apparatus or the insertion of other devices / apparatuses between these two explicitly mentioned devices / apparatuses, unless otherwise specified. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or the scope of implementation of this application. Changes or adjustments in their relative relationships shall also be regarded as the scope of implementation of this application without substantial changes in the technical content.

[0067] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0068] In the description of the present application, it should be understood that the terms "upper", "lower", "left", "right", "inner", "outer", "axial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "multiple" means two or more.

[0069] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0070] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0071] The present application is further described below in conjunction with specific embodiments, but the protection scope of the present application is not limited thereto.

[0072] like Figure 2 to Figure 4 As shown, the friction machine for testing the multi-condition tribological properties of materials according to the present invention comprises:

[0073] Test bench 1;

[0074] The first friction mechanism 2 comprises a first friction member 21, a friction member position regulator 22 for accommodating and fixing the first friction member 21, and a lifting drive mechanism 23 disposed on the test bench 1 for driving the friction member position regulator 22 to lift;

[0075] The second friction mechanism 3 comprises a second friction member 31 and a rotation driving mechanism 32 disposed on the test bench 1 for carrying and driving the second friction member 31 to rotate horizontally;

[0076] A load applying mechanism 4, disposed on the test bench 1, for applying a load to the first friction member 21 so that the first friction member 21 and the second friction member 31 maintain surface contact during the test; and / or

[0077] The detection mechanism 5 is arranged on the test bench 1, and comprises a controller and a friction detection unit 51 connected to the controller. The controller calculates the tribological parameters of the friction pair under multiple working conditions according to the load data detected by the friction detection unit.

[0078] like Figure 5 As shown, the friction member position regulator 22 includes a sample support frame guiding element 221, a sample fixing assembly 222 and an oil tank 228. The sample support frame guiding element 221 is connected to the lifting drive mechanism 23 to drive the sample fixing assembly 222 to move up and down; the sample fixing assembly 222 is adjustably arranged in the sample support frame guiding element 221, and a sample cavity for the first friction member 21 to enter and exit is provided at the lower part of the sample fixing assembly 222. A liquid storage cavity 223 is provided between the top of the sample fixing assembly 222 and the sample support frame guiding element 221, and the liquid storage cavity 223 is connected to the sample cavity and the oil tank 228.

[0079] like Figure 5 As shown, the sample support guide element 221 is a U-shaped structure with its opening facing the test bench 1 .

[0080] like Figure 2 As shown, the two opposite side walls of the sample support guide element 221 are symmetrically provided with horizontal through grooves 2211. During the experiment, the first friction member 21 is mounted on the sample fixing assembly 222, and the sample fixing assembly 222 is fixed at a required distance from the center of the second friction member 31 through the horizontal through grooves 2211 using a buckle. As shown in the figure, the sample fixing assembly 222 includes a sample support frame 2221, a tightening sleeve 2222, a cover 2223 and a buffer member 2224. The sample support frame 2221 is installed in the sample support frame guiding element 221. The end surface of the sample support frame 2221 away from the test bench 1 is provided with a recess, and the recess and the inner surface of the sample support frame guiding element 221 together define a liquid storage chamber 223; the tightening sleeve 2222 and the cover 2223 are coaxially installed in the sample support frame 2221, and together define a sample chamber with a bottom end open for the first friction member 21 to enter and exit; the buffer member 2224 is connected to the inner surface of the cover 2223 facing the workbench, and is used to prevent the first friction member 21 from directly contacting the cover 2223.

[0081] like Figure 5As shown, the sample holder 2221 is installed in the sample holder guide element 221, so that the first friction member 21 can occupy a desired position relative to the friction surface of the second friction member 31 after being pressed. As shown in the figure, the adapter sleeve 2222 is provided with a sleeve that passes through from top to bottom, the top of the adapter sleeve 2222 is provided with an internal thread, the cover 2223 is provided with an external thread that can be threadedly connected with the internal thread, the adapter sleeve 2222 and the cover 2223 are threadedly connected, and together define a sample cavity for accommodating the first friction member; the adapter sleeve 2222 is inserted into the sample holder 2221, and an annular gap is provided between the outer cylindrical surface of the adapter sleeve 2222 and the inner cylindrical surface of the sample holder 2221, so as to allow the first friction member 21 to move axially during the running-in process and in the normal friction and wear mode.

[0082] like Figure 5 As shown, the cross section of the recess is circular, and the center of the recess protrudes upward toward the inner bottom surface away from the test bench 1 to form a convex seat 2220, and the end surface of the convex seat away from the test bench 1 is processed with a first arc groove 2225; the inner surface of the sample support guide element 221 facing the test bench 1 is processed with a second arc groove 2213, and the first arc groove 2225 and the second arc groove 2213 are arranged opposite to each other up and down, and a spherical support member 224 is sandwiched between the two. Preferably, the spherical support member is a steel ball supported between the first arc groove 2225 and the second arc groove 2213, and its diameter is smaller than the diameter of the first arc groove 2225 and the second arc groove 2213. The top and bottom of the spherical support member are in contact with the first arc groove 2225 and the second arc groove 2213 respectively, which can ensure the precise axial load on the first friction member and the ability of its friction surface to self-align with the friction surface of the second friction member during the study.

[0083] like Figure 5 As shown, a working chamber 225 is defined between the sample support 2221 and the cover 2223, and a plurality of grooves 2226 are processed on the inner wall of the adapter sleeve 2222. The working chamber 225 is connected with the liquid storage chamber 223 and the grooves 2226, so as to fill the lubricant in the liquid storage chamber 223 between the first friction member 21 and the second friction member 31.

[0084] like Figure 5 As shown, a connecting hole 2227 is provided inside the sample support frame 2221 , one end of the connecting hole 2227 is connected to the oil storage cavity 223 , and the other end is connected to the working cavity.

[0085] like Figure 6 and Figure 7As shown, the groove 2226 is a V-shaped through groove extending along the central axis of the adapter sleeve, and the notch of the V-shaped through groove faces the central axis of the adapter sleeve.

[0086] like Figure 5 As shown, the top of the sample support guide element 221 is provided with a liquid adding hole 2212 connected to the liquid storage cavity 223. Preferably, the liquid adding hole is a tapered hole with a larger top and a smaller bottom. The lubricant from the oil tank is supplied to the liquid storage cavity 223 formed on the top of the sample fixing component 222 through a pipeline with a control valve and the liquid adding hole, and enters the working cavity from the liquid storage cavity 223 through the connecting hole 2227. The lubricant then directly enters the contact area along the axis direction of the adapter sleeve through several grooves 2226 processed on the inner wall of the adapter sleeve.

[0087] like Figure 5 As shown, the buffer member 2224 is a spring, one end of which is connected to the cover, and the other end of which abuts against the end face of the first friction member 21 movably inserted in the sample cavity away from the test bench, so as to ensure that during the test, the end face of the first friction member close to the test bench is always in contact with and pressed against the second friction member.

[0088] like Figure 5 As shown, the first friction member 21 is a cylindrical friction member movably inserted into the sample cavity. The diameter of the first friction member 21 is 2-11.2 mm, and the height is 0.1-25 mm.

[0089] like Figure 5 As shown, the cross-section of the sample cavity is circular, and the outer diameter of the first friction member 21 is slightly smaller than the inner diameter of the sample cavity, so as to ensure that the first friction member can freely enter and exit the sample cavity along the axis of the sample cavity, thereby reducing the dynamic load during the tribological test of the anti-friction material and lubricant mixture.

[0090] like Figure 2 and Figure 3 As shown, the second friction member 31 is a disc friction member, and the surface of the second friction member away from the test bench is a horizontal friction surface. The diameter of the second friction member 31 is 100-250 mm, and the thickness is 7 mm.

[0091] like Figure 2As shown, the rotation drive mechanism 32 includes a hydraulic motor 321, which is installed on the test bench 1. The output shaft of the hydraulic motor 321 is equipped with a storage cup 322 with an open top, and the second friction member 31 is detachably installed in the storage cup 322. The hydraulic motor 321 has a built-in tachometer, which can measure the rotation speed of the second friction member 31 in real time. The second friction member 31 is fixed to the storage cup 322 by a locking screw 323, so that the storage cup 322 and the second friction member 31 can remain relatively still. During the test, the hydraulic motor 321 can drive the second friction member 31 to have two motion modes, namely, a forward rotation mode or a reverse rotation mode, by rotating clockwise or counterclockwise to test the tribological performance of the friction pair under different working conditions.

[0092] like Figure 2 As shown, the lifting drive mechanism 23 includes a pair of supporting frames 231 arranged opposite to each other, and a gear rack transmission assembly is arranged inside the supporting frame 231. The gear rack transmission assembly includes mutually meshing gears and racks. The gears are rotatably mounted on the supporting frame and connected to the driving motor; the racks are mounted on the supporting frame, and the two racks are connected to a rotating shaft 232; the rotating shaft 232 is located directly above the second friction member, and the rotating shaft is connected to the sample support frame guiding element 221 through a connecting shaft. The driving motor drives the gear to rotate, and the gear drives the rack to rise and fall in the vertical direction, thereby driving the rotating shaft to rise and fall.

[0093] like Figure 2 As shown, the lifting drive mechanism 23 includes a pair of supporting frames 231 arranged opposite to each other, and the lifting adjustment members are adjustably mounted on the supporting frames 231, and a rotating shaft 232 is connected between the two lifting adjustment members; the rotating shaft 232 is located directly above the second friction member, and the rotating shaft 232 is connected to the sample support frame guide element 221 through a connecting shaft 233. The lifting adjustment members are adjusted to a suitable position and then locked. Since the rotating shaft is connected to the lifting adjustment members, the lifting and lowering can be synchronized while the lifting and lowering adjustment members are adjusted.

[0094] like Figure 2 As shown, the load applying mechanism 4 includes a bracket 41, a power load rod 42, a weight 43 and a counterweight 44. The power load rod 42 is an unequal-arm lever, which is pivotally connected to the bracket 41 through a pivot shaft. The counterweight 44 is detachably mounted on the short arm end of the power load rod 42, and a weight plate is hung on the long arm end of the power load rod 42 through a suspension rod. The weight 43 is placed in the weight plate to adjust the load applied between the first friction mechanism 2 and the second friction mechanism 3. In order to reduce the influence of the deadweight of the power load rod 42 and the sample support frame guide element 221, together with the first friction member 21, the adapter sleeve 2222, the buffer member 2224, and the second friction member 31, corresponding counterweights 44 are respectively provided for the force in the contact area between the first friction member 21 and the second friction member 31.

[0095] like Figure 2 As shown, the friction force detection unit 51 includes a strain gauge 511, a tension beam 512, a force transmission rod 513 and a bearing 514. The other end of the force transmission rod 513 is connected to the test end of the strain gauge 511 through the tension beam 512, and one end of the force transmission rod 513 is connected to the sample support frame guide element 221; the bearing 514 is located directly below the power load rod 42, and the bearing 514 is rotatably mounted on the top of the sample support frame guide element 221, and is used to transmit the pressure applied by the power load rod 42 to the strain gauge 511 through the force transmission rod 513. During the test, a weight is placed on the weight plate of the power load rod 42, so that the long arm section of the power load rod 42 stops on the bearing 514 to apply pressure in the direction of the test bench, and the bearing 514 transmits the pressure to the force transmission rod 513 and the tension beam 512, and then to the strain gauge 511 for measurement. During the test, the friction force between the first friction member 21 and the second friction member 31 is measured by the deformation of the tension beam and the strain sensor of the strain gauge 511. The ratio of the friction force to the normal load determines the friction coefficient, and the wear degree is determined by the weight method.

[0096] like Figure 2 As shown, the top of the sample support frame guiding element 221 is provided with a first connecting seat 2214 and a second connecting seat 2215 which are arranged opposite to each other along the axis direction of the sample support frame guiding element 221 , and a bearing is rotatably mounted on the first connecting seat 2214 .

[0097] like Figure 2 As shown, the first connecting seat 2214 is a U-shaped seat integrally formed on the sample support guide element 221 .

[0098] like Figure 2 As shown, the second connecting seat 2215 is an F-shaped seat integrally formed on the sample support guide element 221, and the lateral opening groove of the F-shaped seat is clamped on the outside of the rotating shaft and is pivotally connected to the rotating shaft through the connecting shaft.

[0099] In some embodiments of the present invention, the friction machine of the present invention further comprises a housing, and the test bench 1, the first friction mechanism 2, the second friction mechanism 3, the load applying mechanism 4 and the detection mechanism 5 are all located in the housing. The housing is made of steel, has high overall rigidity, can significantly reduce vibration and noise, especially the vibration and noise of the first friction mechanism, the second friction mechanism and the load applying mechanism, and ensures objective data when studying the friction and wear process.

[0100] In some embodiments of the present invention, the detection mechanism further includes a resistance detection unit for detecting the contact resistance between the first friction member and the second friction member.

[0101] In some embodiments of the present invention, the friction machine of the present invention further includes a thermocouple for measuring the temperature of the contact area between the first friction member and the second friction member. The thermocouple can be arranged on the first friction member or the second friction member. In this embodiment, the thermocouple is arranged on the first friction member, and a hole is formed at the end of the first friction member close to the test bench. The thermocouple is placed in the hole, and the distance between the thermocouple and the contact area is about 0.5 mm.

[0102] As shown in the figure, the present invention also provides a test method using the friction machine for testing the tribological properties of materials and lubricants, comprising the steps of:

[0103] S1 determines the size of the friction surfaces of the first friction member and the second friction member based on the materials, specified precision and quality parameters of the first friction member and the second friction member, and cuts the materials into the first friction member and the second friction member;

[0104] S2: placing the first friction member in the sample chamber, placing the second friction member in the placement cup and fixing it to the placement cup, and adding a proper amount of lubricant into the oil tank;

[0105] S3: adjusting the position of the first friction member so that the first friction member contacts the second friction member at a set position;

[0106] S4 adjusts the state of the friction machine according to the test conditions, applies the load required for the test through the load applying mechanism, sets the test speed and then drives the second friction member to rotate horizontally to perform a friction test, the friction force detection unit obtains the load data applied between the first friction member and the second friction member, the rotation driving mechanism obtains the real-time rotation speed of the second friction member, and the controller calculates the tribological parameters of the friction pair under various working conditions; the tribological parameters at least include friction force.

[0107] The test conditions at least include dry friction conditions (i.e., the contact area is in a state without lubricant) and lubricated conditions (i.e., the contact area is in a state with lubricant), wherein the test under the lubricated condition includes the following steps:

[0108] Lubricant is fed into the contact area between the first friction member and the second friction member.

[0109] Specifically include:

[0110] S5 opens the control valve, and the lubricant in the oil tank flows through the liquid storage chamber and the working chamber in sequence and then fills the contact area between the first friction member and the second friction member;

[0111] S6 applies the load required for the test through the load applying mechanism. The rotary drive mechanism sets the test speed and drives the second friction member to rotate horizontally for a friction test. The friction force detection unit obtains the load data applied between the first friction member and the second friction member. The rotary drive mechanism obtains the real-time rotation speed of the second friction member. The controller calculates the tribological parameters under the lubricant-free state and various force parameters.

[0112] After completing the research cycle, S7 turns off the hydraulic motor and unloads the weight from the power load rod 42 so that the power load rod 42 is separated from the bearing 7;

[0113] S8: close the control valve, stop the lubricant supply, adjust the position of the friction member position regulator, so that the first friction member 21 is disengaged from the second friction member 31, and then remove the first friction member 21 from the adapter sleeve;

[0114] S9 All surfaces of the first friction member 21 and the second friction member 31 are cleaned and prepared for further tribological studies.

[0115] For example, the structure of the friction surface of the first friction member 21 and the second friction member 31 is subjected to metallographic testing. If necessary, the sample is weighed. The present invention studies the characteristics of the composite materials under dry friction conditions (without lubricant) and under conditions of using lubricants in a wide range of stable changes in the speed-force parameters of the friction interaction.

[0116] The tribological parameters also include wear value, friction coefficient, contact zone temperature, contact resistance of the friction pair and friction torque.

[0117] The wear rate is determined at a given sliding speed and load according to formula (1):

[0118]

[0119] Where Δm is the weight wear (unit: mg), L is the friction path (unit: km), and ρ is the material density (unit: g / cm 3 ), S is the friction area (unit: cm 2 ).

[0120] Wear resistance is the inverse of wear rate and is determined by formula (2):

[0121]

[0122] The friction coefficient f is determined according to formula (3):

[0123]

[0124] Among them, P TP is the friction force (unit: N); P is the load force (unit: N).

[0125] The force parameters include sliding speed and specific load.

[0126] The sliding speed is measured according to the position of the first friction member relative to the center of the second friction member, and the calculation formula (4) is as follows:

[0127]

[0128] Where n is the rotation frequency of the reference sample (unit, r / min); R is the distance of a given position of the test sample from the center of the counter-sample (unit, m).

[0129] The load on the test sample is calculated from the force P applied on the dynamic load rod. The ratio of the arms L1, L2 of the dynamic load rod and the ratio of the arms L3, L4 of the sample support guide element are taken into account. Based on the ratios and force P shown above, the load on the first friction member is determined. The specific load on the first friction member is calculated from the ratio, where S is the friction area. The sliding speed is calculated to be 0.2 to 12 m / s and the specific load is 0.15 to 40 MPa.

[0130] The above examples are for the purpose of illustrating the embodiments disclosed in the present application and should not be construed as limiting the present application. In addition, the various modifications listed herein and the variations of methods and compositions in the invention are obvious to those skilled in the art without departing from the scope and spirit of the present application. Although the present application has been specifically described in conjunction with various specific preferred embodiments of the present application, it should be understood that the present application should not be limited to these specific embodiments. In fact, various modifications obvious to those skilled in the art as described above to obtain inventions should be included within the scope of the present application.

Claims

1. A friction machine for testing the tribological properties of materials under multiple working conditions, characterized in that: Comprising: A test bench (1); A first friction mechanism (2), including a first friction member (21), a friction member position adjuster (22) for accommodating and fixing the first friction member (21), and a lifting drive mechanism (23) disposed on the test bench (1) for driving the friction member position adjuster (22) to lift and lower; A second friction mechanism (3), including a second friction member (31) and a rotation drive mechanism (32) disposed on the test bench (1) for carrying and driving the second friction member (31) to rotate horizontally; A load applying mechanism (4), disposed on the test bench (1), for applying a load to the first friction member (21) so that the first friction member (21) and the second friction member (31) maintain surface contact during the test; and / or A detection mechanism (5), disposed on the test bench (1), including a controller and a friction force detection unit (51) connected to the controller, and the controller calculates the tribological parameters of the friction pair under multiple working conditions according to the load data detected by the friction force detection unit.

2. The friction machine for testing the multi-condition tribological properties of materials according to claim 1, characterized in that: The friction member position adjuster (22) includes a sample support frame guiding element (221), a sample fixing assembly (222), and an oil tank (228). The sample support frame guiding element (221) is connected to the lifting drive mechanism (23) for driving the sample fixing assembly (222) to lift and lower. The sample fixing assembly (222) is adjustably disposed in the sample support frame guiding element (221). A sample cavity for the first friction member (21) to enter and exit is provided at the lower part of the sample fixing assembly (222). A liquid storage cavity (223) is provided between the top of the sample fixing assembly (222) and the sample support frame guiding element (221). The liquid storage cavity (223) is communicated with the sample cavity and the oil tank (228).

3. The friction machine for testing the multi-condition tribological properties of materials according to claim 2, characterized in that: The sample support frame guiding element (221) is a U-shaped structure with an opening facing the test bench (1). Horizontally penetrating grooves (2211) are symmetrically provided on the opposite side walls of the sample support frame guiding element (221). A liquid filling hole (2212) communicating with the liquid storage cavity (223) is provided at the top of the sample support frame guiding element (221).

4. The friction machine for testing the multi-condition tribological properties of materials according to claim 2, characterized in that: The sample fixing assembly (222) includes a sample support frame (2221), a locking sleeve (2222), a sealing cover (2223), and a buffer member (2224). The sample support frame (2221) is slidably installed in the sample support frame guiding element (221). A recess is provided on the end face of the sample support frame (2221) away from the test bench (1). The recess and the inner surface of the sample support frame guiding element (221) jointly define the liquid storage cavity (223). The locking sleeve (2222) and the sealing cover (2223) are coaxially installed in the sample support frame (2221) to jointly define a sample cavity with an open bottom for the first friction member (21) to enter and exit. The buffer member (2224) is connected to the inner surface of the sealing cover (2223) facing the workbench to prevent the first friction member (21) from directly contacting the sealing cover (2223).

5. The friction machine for testing the multi-condition tribological properties of materials according to claim 4, characterized in that: The center of the recess protrudes toward the side away from the test bench (1) to form a convex seat (2220), and the end surface of the convex seat away from the test bench (1) is processed with a first arc groove (2225); the inner surface of the sample support guide element (221) facing the test bench (1) is processed with a second arc groove (2213), the first arc groove (2225) and the second arc groove (2213) are arranged opposite to each other in upper and lower parts, and a spherical support member (224) is sandwiched between the two.

6. The friction machine for testing the multi-condition tribological properties of materials according to claim 4, characterized in that: A working chamber (225) is defined between the sample support frame (2221) and the sealing cover (2223); the inner wall of the adapter sleeve (2222) is processed with a plurality of grooves (2226); the working chamber (225) is connected with the liquid storage chamber (223) and the grooves (2226) and is used to fill the lubricant in the liquid storage chamber (223) between the first friction member (21) and the second friction member (31).

7. The friction machine for testing the multi-condition tribological properties of materials according to claim 1, characterized in that: The rotary drive mechanism (32) comprises a hydraulic motor (321), the hydraulic motor (321) is mounted on the test bench (1), the output shaft of the hydraulic motor (321) is equipped with a storage cup (322) with an open top, and the second friction member (31) is detachably mounted in the storage cup (322).

8. The friction machine for testing the multi-condition tribological properties of materials according to claim 1, characterized in that: The load applying mechanism (4) comprises a bracket (41), a power load rod (42), a weight (43) and a counterweight (44); the power load rod (42) is pivotally connected to the bracket (41) via a pivot shaft; the counterweight (44) is arranged at the short arm end of the power load rod (42); a weight (43) plate is hung at the long arm end of the power load rod (42) via a suspension rod; a weight (43) plate is placed in the weight (43) plate for adjusting the load applied between the first friction mechanism (2) and the second friction mechanism (3).

9. The friction machine for testing the multi-condition tribological properties of materials according to claim 1, characterized in that: The friction force detection unit (51) comprises a strain gauge (511), a tension beam (512), a force transmission rod (513) and a bearing (514); the other end of the force transmission rod (513) is connected to the test end of the strain gauge (511) through the tension beam (512); one end of the force transmission rod (513) is connected to the sample support frame guide element (221); the bearing (514) is located directly below the dynamic load rod (42); the bearing (514) is rotatably mounted on the top of the sample support frame guide element (221) and is used to transmit the pressure applied by the dynamic load rod (42) to the strain gauge (511) via the force transmission rod (513).

10. A test method using the friction machine for testing the multi-condition tribological properties of materials as claimed in any one of claims 1 to 9, characterized in that: Includes steps: Determine the size of the friction surfaces of the first friction member and the second friction member based on the materials, specified precision and quality parameters of the first friction member and the second friction member, and cut the materials into the first friction member and the second friction member; The first friction member is placed in the sample cavity, the second friction member is placed in the placement cup and fixed to the placement cup, and lubricant is added into the oil tank; Adjusting the position of the first friction member so that the first friction member contacts the second friction member at a set position; The friction machine state is adjusted according to the test conditions, the load required for the test is applied by the load applying mechanism, the rotary drive mechanism sets the test speed and then drives the second friction member to rotate horizontally to perform the friction test, the friction force detection unit obtains the load data applied between the first friction member and the second friction member, the rotary drive mechanism obtains the real-time rotation speed of the second friction member, and the tribological parameters of the friction pair under each working condition are calculated by the controller; the tribological parameters at least include friction force.

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