Ultrahigh-speed sliding dry friction test device and test method

Abstract

The invention provides an ultra-high-speed sliding dry friction test device and a test method, and the test device comprises a metal sliding block formed by processing a to-be-tested material, an electromagnetic acceleration mechanism, a sliding friction wear mechanism, a speed measurement mechanism and a pressure measurement mechanism, the electromagnetic acceleration mechanism comprises a pulse power supply and two electromagnetic tracks connected with the positive electrode and the negative electrode of the pulse power supply respectively. The sliding friction and abrasion mechanism comprises two friction pairs which are arranged in parallel up and down, a sliding channel for the metal sliding block to slide through is arranged between the two friction pairs, and the friction pair and the electromagnetic rail which are located on the same side are consistent in axis; the speed measuring mechanism comprises a velometer A and a velometer B which are respectively arranged at an inlet and an outlet of the sliding channel; the pressure measuring mechanism comprises a pressure sensor A and a pressure sensor B which are arranged on the upper and lower sides of the sliding channel in the sliding direction; by means of the test device, the dry friction speed of the metal sliding block after the metal sliding block leaves the electromagnetic acceleration mechanism can be above 103 m / s, and then the friction force and the friction coefficient of the metal sliding block can be calculated.

Description

Technical Field

[0001] The invention relates to the field of dry friction and wear, in particular to an ultra-high-speed sliding dry friction test device and a test method. Background Art

[0002] High-speed sliding friction and wear are widely found in engineering fields such as gun rifling, hypersonic rocket skids, high-speed train wheel-rail contact, and train brakes. The friction and wear of the contact interface is an important factor affecting the friction performance of materials and the service life of equipment. At present, for the relevant research on the friction and wear of the above-mentioned equipment, the mainstream technical means in the field of tribology is still to conduct simulation tests with the help of test equipment. However, due to the limitation of the motor speed, the sliding linear speed of the pin-on-disk testing machine is difficult to reach more than 100m / s, while the launch process speed of equipment such as guns, artillery, and hypersonic rocket skids can reach 800m / s or even more than 2000m / s. The traditional pin-on-disk testing machine can no longer meet the technical requirements of the above-mentioned engineering fields.

[0003] Therefore, it is urgent to propose an ultra-high-speed sliding dry friction test device and its supporting test method to solve the above technical problems. Summary of the invention

[0004] In order to solve the deficiencies in the prior art, the present invention provides an ultra-high-speed sliding dry friction test device and a test method. The test device of the present invention can make the dry friction speed of the metal slider after leaving the electromagnetic acceleration mechanism within 10 3 The value is above the m / s level, and the friction force and friction coefficient of the metal slider can be calculated.

[0005] In order to achieve the above object, the specific scheme adopted by the present invention is: In one aspect, the present invention provides an ultra-high-speed sliding dry friction test device, comprising: Metal slider, made of the material to be tested; The electromagnetic acceleration mechanism is used to provide power for the sliding of the metal slider; it includes a pulse power supply and two electromagnetic tracks connected to the positive and negative electrodes of the pulse power supply respectively, the two electromagnetic tracks are arranged in parallel up and down and are arranged opposite to each other with a gap, and the metal slider is located in the gap between the two electromagnetic tracks in the initial state; The sliding friction wear mechanism is connected to one end of the electromagnetic acceleration mechanism, and includes two friction pairs arranged in parallel up and down, and a sliding channel for a metal slider to slide through is provided between the two friction pairs. The metal slider can slide along the sliding channel in a direction away from the electromagnetic track under the action of the electromagnetic acceleration mechanism. The two friction pairs are connected to the electromagnetic track on the same side through an insulating track, and the axes of the friction pairs, the insulating track and the electromagnetic track on the same side are consistent; The speed measuring mechanism is used to measure the speed of the metal slider, including a speed measuring device A arranged at the entrance of the sliding channel and a speed measuring device B arranged at the exit of the sliding channel; The pressure measuring mechanism is used to measure the pressure value when the metal slider slides through the sliding channel, including a pressure sensor A arranged on the upper side of the sliding channel in the sliding direction and a pressure sensor B arranged on the lower side of the sliding channel in the sliding direction.

[0006] Furthermore, it also includes a supporting and fixing mechanism, which includes an insulating block, the pressure sensor A and the pressure sensor B are respectively arranged on the upper and lower sides of the insulating block, a through groove is provided in the middle of the insulating block, two insulating plates are provided in the through groove, the two insulating plates are arranged in parallel front and back and are relatively spaced, and two friction pairs, two insulating rails and two electromagnetic rails are sequentially arranged at the upper and lower ends of the two insulating plates.

[0007] Furthermore, upper step grooves and lower step grooves are provided on the opposite sides of the two insulating plates, wherein the friction pair, insulating track and electromagnetic track located above are sequentially arranged between the two upper step grooves, and the friction pair, insulating track and electromagnetic track located below are sequentially arranged between the two lower step grooves.

[0008] Furthermore, the insulating block is composed of four insulators, including a first insulator and a second insulator stacked up and down and fixed by fixing blocks located on the front and rear sides thereof, and a third insulator and a fourth insulator stacked up and down, the first insulator and the second insulator cooperate with the friction pair and the insulating track, and the third insulator and the fourth insulator cooperate with the electromagnetic track.

[0009] Furthermore, a shell is provided on the outside of the supporting and fixing mechanism, and the shell consists of two symmetrically arranged half shells connected by bolts to wrap and press the supporting and fixing mechanism located inside thereof.

[0010] Furthermore, the speed of the metal slider in the sliding channel can reach 10 3 Above m / s level.

[0011] On the other hand, the present invention also provides an ultra-high speed sliding dry friction test method, which uses the ultra-high speed sliding dry friction test device to conduct the test, and mainly includes the following steps: S1. Install the metal slider in the gap between the two electromagnetic tracks and set the voltage of the pulse power supply; S2, collecting the moving speed of the metal slider measured by the speed measuring mechanism and the pressure value measured by the pressure measuring mechanism, and calculating the friction force and friction coefficient of the metal slider; S3, tribological analysis of the metal slider; S4. By setting different pulse voltages or continuously testing the same friction pair material, repeating S1-S3, and conducting ultra-high-speed sliding friction and wear tests at different speeds and different numbers of cycles, the friction and wear performance of the metal slider can be finally obtained.

[0012] Furthermore, the speed meter A measures the speed of the metal slider at the entrance of the sliding channel, the speed meter B measures the speed of the metal slider at the exit of the sliding channel, and the pressure sensor A and the pressure sensor B are used to measure the pressure value. Then, in step S2, the calculation formula of the friction force and the friction coefficient is: Where: m is the mass of the metal slider, v A is the speed measured by speedometer A, v B is the speed measured by speedometer B, F f is the friction force at both ends of the metal slider, s is the length of the friction pair, f is the friction coefficient at the upper and lower ends of the metal slider, F A is the pressure value measured by pressure sensor A, F B is the pressure value measured by pressure sensor B.

[0013] Beneficial effects:

[0014] (1) The present invention uses an electromagnetic acceleration mechanism to accelerate the metal slider. By setting the output voltage of the pulse power supply, the dry friction speed of the metal slider after leaving the electromagnetic acceleration mechanism can reach 10 3 m / s level, much higher than the current sliding pin-disc testing machine (10 2 m / s level).

[0015] (2) The present invention is based on the principle of conservation of energy. The friction force of the metal slider is calculated by measuring the sliding speed of the metal slider passing between speed meter A and speed meter B. The friction coefficient of the metal slider is obtained by measuring the pressure change when the metal slider passes through the friction pair.

[0016] (3) The test efficiency of the present invention is high. By setting different pulse voltages or continuously testing the same friction pair material, ultra-high-speed sliding friction and wear tests at different speeds and different numbers of cycles can be carried out to obtain the friction and wear performance of the material under different high-speed conditions and continuous wear. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the test device in the present invention.

[0018] Figure 2 It is a schematic diagram of the test friction device in the present invention.

[0019] Figure 3 It is a main cross-sectional view of the test device in the present invention.

[0020] Figure 4 Schematic diagram of the insulating plate in the present invention.

[0021] Graphic markings: 1. Pulse power supply, 2. Electromagnetic track, 3. Insulated track, 4. Speed ​​meter A, 5. Friction pair, 5-1. Sliding channel, 6. Metal slider, 7. Speed ​​meter B, 8. Pressure sensor A, 9. Housing, 10. Pressure sensor B, 11. Insulating plate, 11-1. Upper step groove, 11-2. Lower step groove, 12. Insulating block, 12-1. Through groove, 1201. First insulator, 1202. Second insulator, 1203. Third insulator, 1204. Fourth insulator, 13. Fixed block. DETAILED DESCRIPTION

[0022] The technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0023] In the description of the present invention, it is necessary to understand that the terms "upper" and "lower" etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention 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 limiting the scope of protection of the present invention.

[0024] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0025] The present invention provides an ultra-high speed sliding dry friction test device, please refer to Figure 1 and Figure 2The test device includes a housing 9, a supporting and fixing mechanism, an electromagnetic acceleration mechanism, a sliding friction and wear mechanism, an insulating track 3, a speed measuring mechanism, a pressure measuring mechanism, and a metal slider 6 made of a material to be tested. The friction force and friction coefficient of the metal slider 6 can be measured by the test device. The specific structure of each part or mechanism is described in detail below.

[0026] <Electromagnetic Acceleration Mechanism>

[0027] The electromagnetic acceleration mechanism is used to provide power for the sliding of the metal slider 6. The electromagnetic acceleration mechanism includes a pulse power supply 1 and two electromagnetic tracks 2. One end of the two electromagnetic tracks 2 is respectively connected to the positive and negative poles of the pulse power supply 1. The two electromagnetic tracks 2 are arranged in parallel up and down and are relatively spaced apart. In the initial state, the metal slider 6 is located in the gap between the two electromagnetic tracks 2.

[0028] The electromagnetic acceleration mechanism can set the output voltage of the pulse power supply 1 to make the speed of the metal slider 6 reach 10 3 Above m / s level.

[0029] <Insulation Track 3>

[0030] There are two insulating rails 3, which are arranged up and down and spaced apart from each other. The two insulating rails 3 are respectively connected to one end of the electromagnetic rail 2 on the same side away from the pulse power supply 1, and the axes of the insulating rail 3 and the electromagnetic rail 2 on the same side are consistent.

[0031] <Sliding Friction and Wear Mechanism>

[0032] The sliding friction wear mechanism is connected to the electromagnetic acceleration mechanism through the insulating track 3. The sliding friction wear mechanism is connected to one end of the electromagnetic acceleration mechanism, and includes two friction pairs 5 arranged in parallel up and down, the friction pairs 5 are made of the test material, and there is a sliding channel 5-1 between the two friction pairs 5 for the metal slider 6 to slide through. The metal slider 6 can slide along the sliding channel 5-1 in the direction away from the electromagnetic track 2 under the action of the electromagnetic acceleration mechanism. The two friction pairs 5 are connected to the electromagnetic track 2 on the same side through the insulating track 3, and the axes of the friction pairs 5, the insulating track 3 and the electromagnetic track 2 on the same side are consistent.

[0033] The current conducted by the electromagnetic track 2 passes through the friction pair 5, which will cause the contact between the metal slider 6 and the friction pair 5 to change from dry friction to current-carrying friction. Therefore, the two friction pairs 5 cannot directly contact each other. Instead, the insulating track 3 is used to guide the metal slider 6 after leaving the electromagnetic track 2 into the sliding friction wear mechanism.

[0034] <Speed ​​Measuring Mechanism>

[0035] The speed measuring mechanism is used to measure the speed of the metal slider 6, including a speed meter A4 and a speed meter B6; the speed meter A4 is arranged at the entrance of the sliding channel 5-1 and installed between the two insulating rails 3, and is used to measure the initial speed of the metal slider 6 when entering the sliding channel 5-1; the speed meter B6 is installed at the exit of the sliding channel 5-1, and is used to measure the final speed of the metal slider 6 when leaving the sliding channel 5-1.

[0036] <Pressure Measuring Mechanism>

[0037] The pressure measuring mechanism is used to measure the pressure value when the metal slider 6 slides through the sliding channel 5-1, including a pressure sensor A8 arranged on the upper side of the sliding channel 5-1 in the sliding direction and a pressure sensor B10 arranged on the lower side of the sliding channel 5-1 in the sliding direction.

[0038] Under static conditions, the pressure sensor A8 and the pressure sensor B10 can also be used to measure the elastic preload force of the interference metal slide block 6 between the two friction pairs 5 .

[0039] <Support and fixing mechanism>

[0040] The supporting and fixing mechanism is used to support and fix the electromagnetic acceleration mechanism and the sliding friction wear mechanism. The supporting and fixing mechanism includes an insulating block 12. The pressure sensor A8 and the pressure sensor B10 are respectively arranged on the upper and lower sides of the insulating block 12. A through groove 12-1 is provided in the middle of the insulating block 12. Two insulating plates 11 are arranged in the through groove 12-1. The two insulating plates 11 are arranged in parallel front and back and are relatively spaced. Two friction pairs 5, two insulating rails 3 and two electromagnetic rails 2 are arranged at the upper and lower ends of the two insulating plates 11 in sequence.

[0041] Please refer to Figure 4 , upper step grooves 11-1 and lower step grooves 11-2 are provided on opposite sides of the two insulating plates 11, wherein the friction pair 5, insulating track 3 and electromagnetic track 2 located at the upper side are sequentially arranged between the two upper step grooves 11-1, and the friction pair 5, insulating track 3 and electromagnetic track 2 located at the lower side are sequentially arranged between the two lower step grooves 11-2. The sizes of the upper step grooves 11-1 and the lower step grooves 11-2 in the insulating plates 11 are adjustable to meet different track gaps.

[0042] Preferably, in order to facilitate the installation of the electromagnetic acceleration mechanism and the sliding friction wear mechanism, the insulating block 12 can be set as a split structure, please refer to Figure 3The insulating block 12 is composed of four insulators, including a first insulator 1201 and a second insulator 1202 stacked up and fixed by fixing blocks 13 located at the front and rear sides thereof, and a third insulator 1203 and a fourth insulator 1204 stacked up and down. The first insulator 1201 and the second insulator 1202 cooperate with the friction pair 5 and the insulating track 3, and the third insulator 1203 and the fourth insulator 1204 cooperate with the electromagnetic track 2.

[0043] The insulating block 12 , the fixing block 13 , the pressure sensor A 8 and the pressure sensor B 10 form a whole with a regular shape (such as a rectangular parallelepiped), which is convenient for being compressed by the housing 9 .

[0044] <Shell 9>

[0045] The shell 9 is used to compress the supporting and fixing mechanism and the electromagnetic acceleration mechanism and the sliding friction wear mechanism arranged therein. The shell 9 consists of two symmetrically arranged half shells connected by bolts to wrap and compress the supporting and fixing mechanism located therein.

[0046] The following is an explanation of the method of conducting a friction test using the above-mentioned test device. When conducting a tribological test, the following steps are included: S1, assemble the parts of the test device except the metal slider 6 into a whole; S2, install the metal slider 6 between the two electromagnetic tracks 2, and set the voltage of the pulse power supply 1; S3, collect the moving speed of the metal slider measured by the speed meter A4 and the speed meter B6, and the pressure values ​​measured by the pressure sensor A8 and the pressure sensor B10, and calculate the friction force and friction coefficient of the metal slider 6, and the calculation formula is: Where: m is the mass of the metal slider, v A is the speed measured by speedometer A, v B is the speed measured by speedometer B, F f is the friction force at both ends of the metal slider, s is the length of the friction pair, f is the friction coefficient at the upper and lower ends of the metal slider, F A is the pressure value measured by pressure sensor A, F B is the pressure value measured by pressure sensor B; S4, performing tribological analysis on the metal slider 6; S5. By setting different pulse voltages or continuously testing the same friction pair material, repeating S2-S4, ultra-high-speed sliding friction and wear tests at different speeds and different numbers of cycles can be carried out, and finally the friction and wear performance of the metal slider 6 under different high-speed conditions and continuous wear can be obtained.

[0047] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any equivalent changes or modifications made according to the essence of the present invention should be included in the protection scope of the present invention.

Claims

1. An ultra-high-speed sliding dry friction test device, characterized in that: include: Metal slider, made of the material to be tested; The electromagnetic acceleration mechanism is used to provide power for the sliding of the metal slider; it includes a pulse power supply and two electromagnetic tracks connected to the positive and negative electrodes of the pulse power supply respectively, the two electromagnetic tracks are arranged in parallel up and down and are arranged opposite to each other with a gap, and the metal slider is located in the gap between the two electromagnetic tracks in the initial state; The sliding friction wear mechanism is connected to one end of the electromagnetic acceleration mechanism, and includes two friction pairs arranged in parallel up and down, and a sliding channel for a metal slider to slide through is provided between the two friction pairs. The metal slider can slide along the sliding channel in a direction away from the electromagnetic track under the action of the electromagnetic acceleration mechanism. The two friction pairs are connected to the electromagnetic track on the same side through an insulating track, and the axes of the friction pairs, the insulating track and the electromagnetic track on the same side are consistent; The speed measuring mechanism is used to measure the speed of the metal slider, including a speed measuring device A arranged at the entrance of the sliding channel and a speed measuring device B arranged at the exit of the sliding channel; The pressure measuring mechanism is used to measure the pressure value when the metal slider slides through the sliding channel, including a pressure sensor A arranged on the upper side of the sliding channel in the sliding direction and a pressure sensor B arranged on the lower side of the sliding channel in the sliding direction.

2. The ultra-high-speed sliding dry friction test device according to claim 1, characterized in that: It also includes a supporting and fixing mechanism, which includes an insulating block. The pressure sensor A and the pressure sensor B are respectively arranged on the upper and lower sides of the insulating block. A through groove is provided in the middle of the insulating block. Two insulating plates are arranged in the through groove. The two insulating plates are arranged in parallel front and back and are spaced relative to each other. Two friction pairs, two insulating rails and two electromagnetic rails are sequentially arranged at the upper and lower ends of the two insulating plates.

3. The ultra-high-speed sliding dry friction test device according to claim 2, characterized in that: Upper step grooves and lower step grooves are provided on the opposite sides of the two insulating plates, wherein the friction pair, insulating track and electromagnetic track located above are sequentially arranged between the two upper step grooves, and the friction pair, insulating track and electromagnetic track located below are sequentially arranged between the two lower step grooves.

4. The ultra-high-speed sliding dry friction test device according to claim 2, characterized in that: The insulating block is composed of four insulators, including a first insulator and a second insulator stacked up and down and fixed by fixing blocks located on the front and rear sides thereof, and a third insulator and a fourth insulator stacked up and down. The first insulator and the second insulator cooperate with the friction pair and the insulating track, and the third insulator and the fourth insulator cooperate with the electromagnetic track.

5. The ultra-high-speed sliding dry friction test device according to claim 4, characterized in that: An outer shell is provided on the outside of the supporting and fixing mechanism, and the outer shell consists of two symmetrically arranged half shells connected by bolts to wrap and press the supporting and fixing mechanism located inside the outer shell.

6. The ultra-high-speed sliding dry friction test device according to claim 1, characterized in that: The speed of the metal slide in the sliding channel can reach 10 3 Above m / s level.

7. An ultra-high-speed sliding dry friction test method, characterized in that: The ultra-high-speed sliding dry friction test device according to any one of claims 1 to 6 is used to conduct the test, which mainly comprises the following steps: S1. Install the metal slider in the gap between the two electromagnetic tracks and set the voltage of the pulse power supply; S2, collecting the moving speed of the metal slider measured by the speed measuring mechanism and the pressure value measured by the pressure measuring mechanism, and calculating the friction force and friction coefficient of the metal slider; S3, tribological analysis of the metal slider; S4. By setting different pulse voltages or continuously testing the same friction pair material, repeating S1-S3, and conducting ultra-high-speed sliding friction and wear tests at different speeds and different numbers of cycles, the friction and wear performance of the metal slider can be finally obtained.

8. The ultra-high-speed sliding dry friction test method according to claim 7, characterized in that: Speed ​​meter A measures the speed of the metal slider at the entrance of the sliding channel, speed meter B measures the speed of the metal slider at the exit of the sliding channel, and pressure sensor A and pressure sensor B are used to measure the pressure value. In step S2, the calculation formula of the friction force and the friction coefficient is: Where: m is the mass of the metal slider, v A is the speed measured by speedometer A, v B is the speed measured by speedometer B, F f is the friction force at both ends of the metal slider, s is the length of the friction pair, f is the friction coefficient at the upper and lower ends of the metal slider, F A is the pressure value measured by pressure sensor A, F B is the pressure value measured by pressure sensor B.

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