Friction chemical in-situ characterization apparatus and use thereof

Abstract

A friction chemical in-situ characterization apparatus and a use thereof. The apparatus comprises an ATR support member (6), an ATR crystal (5), and a heating module (4), the ATR support member (6) is provided with a sample tank, the ATR support member (6) is provided with an optical path channel communicated with the bottom of the sample tank, the ATR crystal (5) is installed in the optical path channel, and the heating module (4) is arranged on the lower end surface of the ATR crystal (5). The friction chemical in-situ characterization apparatus further comprises a mechanical friction apparatus arranged in the sample tank and above the ATR crystal (5); the mechanical friction apparatus comprises a slide rail (2) secured on the top of the ATR support member (6), an adapter block (3) slidably arranged on the slide rail (2), and a grinding head (1) detachably secured at the lower end of the adapter block (3); the adapter block (3) is provided with a control system, the control system regulates the pressure, movement mode, and grinding speed of the grinding head (1) on the surface of the ATR crystal (5) by controlling the adapter block (3), and acquires a friction coefficient and wear rate data of a sample material.

Description

A tribochemical in-situ characterization device and its application Technical Field

[0001] The present invention relates to the field of analysis and detection, and in particular to a tribochemical in-situ characterization device and application thereof. Background Art

[0002] The attenuated total internal reflection (ATR) accessory is a widely used test accessory in the field of infrared spectrometers. It obtains structural information of the sample attached to the crystal surface through the total internal reflection of light waves within the crystal. It does not require a complicated tableting process and is a convenient and practical infrared spectrometer accessory.

[0003] For example, Chinese patent publication CN101479638A discloses an accessory for a microscope arranged to perform ATR measurement, which has a support member that can be mounted on a movable stage of the microscope, and a mounting member for an ATR crystal is carried on the support member.

[0004] Chinese patent publication number CN 108169186 A discloses an attenuated total internal reflection spectrometer and its application. The accessories include: an ATR crystal component and a support member, the support member is provided with a sample slot, the ATR crystal component includes an ATR crystal; the sample slot has an inner cavity that can accommodate a sample, and the ATR crystal is located above the inner cavity of the sample slot and is connected to the sample slot.

[0005] The ATR accessory features real-time detection or monitoring capabilities, enabling continuous or intermittent sampling of sample information from the ATR crystal surface. For example, the ATR crystal can be used to detect the functional group structure of media such as grease and determine its performance. However, evaluating the performance and lifespan of materials like grease often requires subjecting them to specific operating conditions for a period of time through friction or step tests, with before-and-after comparisons to obtain data. Using existing infrared spectrometer ATR accessories for these tests requires intermittent sampling and thorough cleaning of the ATR crystal after each test, resulting in cumbersome operations and poor data consistency.

[0006] Summary of the Invention

[0007] To solve the problem of monitoring continuity when testing grease using an attenuated total internal reflection (ATR) accessory, the present invention provides a tribochemical in-situ characterization device and application, which can continuously monitor the grease and determine the service life and failure process of the grease.

[0008] A tribochemical in-situ characterization device includes an ATR support member that can be used in a Fourier transform infrared spectrometer, an ATR crystal, and a heating module. The ATR support member includes a sample slot, an optical path communicating with the bottom of the sample slot, the ATR crystal is mounted in the optical path, and the heating module is disposed on the lower end surface of the ATR crystal. The tribochemical in-situ characterization device also includes a mechanical friction device disposed in the sample slot and above the ATR crystal.

[0009] The mechanical friction device includes a horizontal slide rail or an annular slide rail fixed to the top of the ATR support frame, an adapter block slidably arranged on the slide rail, and a grinding head detachably fixed to the lower end of the adapter block. The material, surface roughness, and hardness parameters of the grinding head are set according to experimental requirements; the adapter block is provided with a control system, and the control system controls the adapter block to regulate parameters such as the pressure, movement mode, and grinding speed of the grinding head on the ATR crystal surface, and can collect data such as the friction coefficient and wear rate of the material;

[0010] During the test, the sample is placed in the ATR sample chamber and continuously monitored in situ in real time using a Fourier transform infrared spectrometer. The mechanical friction device's start time is set as the time origin, and the pressure, motion mode, and grinding speed are set according to experimental requirements. Based on the infrared spectrum and data such as the friction coefficient and wear rate collected by the control system, changes in the sample's physical and chemical properties during the friction process are determined in real time. This data further determines damage and failure time to the sample material, thereby assessing the material's service life. Optionally, the end face of the grinding head facing the ATR crystal can be circular, elliptical, or polygonal in shape.

[0011] Optionally, the grinding head is made of stainless steel, cemented carbide, copper alloy, aluminum alloy, titanium alloy, ceramic or diamond.

[0012] Optionally, the ATR crystal is made of optical crystals such as diamond, silicon, germanium, zinc selenide or single crystal aluminum oxide.

[0013] Preferably, the width of the sample groove is 1 mm-20 mm, and the length is 1 cm-10 cm; the width of the end face of the grinding head facing the ATR crystal is smaller than the width of the sample groove, and the length of the end face is smaller than the length of the sample groove.

[0014] Preferably, the mechanical friction device is also provided with grease-removing plates, and the grease-guiding plates are arranged on both sides of the movement direction of the grinding head. The position thereof can be controlled to rise and fall by a control system so that the grease-removing plates behind the grinding head are always located in the groove and work, and the grease squeezed to both sides of the sample groove by the grinding head is pushed back to the middle position to avoid the grease accumulating on both sides of the sample groove during the test, causing the grinding head to "grind in vain".

[0015] Preferably, the control system regulates the unidirectional friction or bidirectional reciprocating friction of the grinding head by controlling the adapter block, the friction speed range is 0.01mm / s-1000mm / s, and the maximum friction stroke is the length of the sample slot.

[0016] Preferably, the heating module is used to heat the sample in the sample tank, and the heating temperature range in the sample tank is 0-200°C.

[0017] The present invention also provides a method for detecting grease indicators, using an infrared spectrometer arranged with the above-mentioned tribochemical reaction in-situ characterization device, and the specific detection process is as follows:

[0018] Apply the grease to be tested to the sample groove on the upper surface of the ATR crystal;

[0019] The operating temperature of the grease is set by the heating module, and the control system rubs the grease on the surface of the ATR crystal by regulating the pressure, movement mode and grinding speed of the grinding head on the surface of the ATR crystal. At the same time, the control system uploads real-time data such as pressure, movement mode and grinding speed to the computer;

[0020] During the friction process of the grease, the infrared light emitted by the infrared spectrometer passes through the optical path channel to irradiate the grease on the upper surface of the ATR crystal. The infrared spectrum monitors the changes in the functional group absorption peaks of the grease during the friction process in real time. Combined with the relevant data of the control system, the chemical reaction of the grease during the friction process is judged;

[0021] The control system monitors the changes in the friction coefficient and wear rate data on the grease interface, and uses infrared spectroscopy to determine the changes in the grease's service performance and the time it takes to fail in real time.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention can monitor the changes in the functional group absorption peaks of grease during the friction process in real time. By monitoring the structural changes of grease during the friction and wear process, the physical and chemical property changes of the sample during the friction process can be judged in real time based on the infrared spectrum and the friction coefficient, wear rate and other data collected by the control system. The damage and failure time of the sample material can be further judged, and the service life of the sample material can be evaluated. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] FIG1 is a schematic structural diagram of a tribochemical in-situ characterization device according to the present invention;

[0026] In the figure: 1-grinding head, 2-horizontal slide, 3-adapter block, 4-heating component, 5-ATR crystal, 6-ATR support. DETAILED DESCRIPTION

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not 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 efforts are within the scope of protection of the present invention.

[0028] As shown in Figure 1, a tribochemical in-situ characterization device includes an ATR support 6 that can be used for a Fourier transform infrared spectrometer, an ATR crystal 5, and a heating module. A sample slot is provided inside the ATR support 6, and an optical path channel connected to the bottom of the sample slot is provided inside the ATR support 6. The ATR crystal 5 is installed in the optical path channel. The heating module is arranged on the lower end surface of the ATR crystal 5 and is used to heat the sample in the sample slot. The heating temperature range in the sample slot is 0-200°C.

[0029] The tribochemical in-situ characterization device also includes a mechanical friction device arranged in the sample tank and above the ATR crystal 5. The mechanical friction device includes a slide rail 2 (horizontal slide rail or annular slide rail) fixed on the top of the ATR support frame 6, an adapter block 3 slidably arranged on the slide rail 2, and a grinding head 1 detachably fixed to the lower end of the adapter block 3. The material, surface roughness, and hardness parameters of the grinding head 1 are set according to experimental requirements. A control system is provided on the adapter block 3. The control system controls the pressure, movement mode, grinding speed and other parameters of the grinding head 1 on the surface of the ATR crystal 5 by controlling the adapter block 3, and can collect data such as the friction coefficient and wear rate of the sample material.

[0030] The ATR crystal 5 is sealed and filled in the optical path, and is sealed with the sample slot. In one embodiment, transmissive windows are provided at both ends of the optical path, through which infrared light can pass. The transmissive windows are used to prevent the ATR crystal 5 from being contaminated by foreign matter and affecting the detection results.

[0031] Alternatively, the end face of the grinding head 1 facing the ATR crystal 5 may be circular, elliptical or polygonal.

[0032] Alternatively, the grinding head 1 may be made of stainless steel, cemented carbide, copper alloy, aluminum alloy, titanium alloy, ceramic or diamond.

[0033] Alternatively, the material of the ATR crystal 5 may be diamond, silicon, germanium, zinc selenide or single crystal aluminum oxide.

[0034] The width of the sample groove can be 1-20 mm and the length can be 1-10 cm. The width of the end face of the grinding head 1 facing the ATR crystal is smaller than the width of the sample groove, and the length of the end face is smaller than the length of the sample groove.

[0035] The control system controls the adapter block 3 to regulate the unidirectional friction or bidirectional reciprocating friction of the grinding head 1. The friction speed and stroke can be regulated by the control system. The friction speed range is 0.01-1000mm / s, the maximum friction stroke is the length of the sample slot, and the grinding path can be regulated by the control system.

[0036] Optionally, the tribochemical in-situ characterization device further comprises a power supply, which is used to provide electrical energy for operating the tribochemical in-situ characterization device.

[0037] The tribochemical in-situ characterization device of the present invention is arranged in an infrared spectrometer to detect grease indicators, comprising the following steps:

[0038] S01, the grease to be tested is applied to the sample slot on the upper surface of the ATR crystal. Figure 2 shows the infrared spectrum of the grease to be tested before friction.

[0039] S02, the working temperature of the grease is set through the heating module, and the control system rubs the grease on the surface of the ATR crystal by adjusting the pressure, movement mode and grinding speed of the grinding head on the surface of the ATR crystal. At the same time, the control system uploads the pressure, movement mode and grinding speed data to the computer in real time.

[0040] During the friction process of the grease in step S03, infrared light from the infrared spectrometer passes through the optical path and illuminates the grease on the upper surface of the ATR crystal. Infrared spectroscopy monitors changes in the functional group absorption peaks of the grease during the friction process in real time, identifying chemical reactions occurring during the friction process. The control system monitors changes in the friction coefficient and wear rate at the grease interface and, combined with infrared spectroscopy, determines changes in the grease's service performance and the time to grease failure in real time.

[0041] Figure 3 shows the infrared spectrum of the grease to be tested after friction. Comparing Figures 2 and 3, it can be seen that the CH on the carbon skeleton of the grease is at 1463 cm -1 The in-plane bending vibration peak is red-shifted to 1459 cm -1 This indicates that the in-plane bending vibration intensity between carbon and hydrogen in the grease is weakened after friction, which affects the lubrication performance. -1 The absorption peak at 1377.54 cm also red-shifted to 1377.54 cm -1It also shows that the in-plane rocking vibration between the carbon-hydrogen bonds of the grease is weakened. -1 and 543cm -1 The absorption peak at 560 cm -1 It is replaced by a broad peak, which also shows that the hydrogen on the carbon skeleton of the grease causes performance loss due to the friction work during the friction process.

[0042] Example 1

[0043] The prepared lithium-based grease was placed in an ATR sample tank to evaluate its friction performance. A 6mm GCr15 steel ball was used as the grinding head, with a load of 1N, a reciprocating frequency of 1Hz, a stroke of 10mm, and friction tests at room temperature for 30 minutes. The average friction coefficient was 0.15.

[0044] Example 2

[0045] The prepared lithium-based grease was placed in an ATR sample chamber to evaluate its friction performance. A 6mm carbide ball was used as the grinding head, with a load of 1N, a reciprocating frequency of 1Hz, and a stroke of 10mm. The friction test was conducted at room temperature for 30 minutes. The average friction coefficient was 0.21.

[0046] Example 3

[0047] The prepared lithium-based grease was placed in an ATR sample chamber to evaluate its friction performance. A 6mm copper alloy ball was used as the grinding head. The test was conducted at room temperature with a load of 1N, a reciprocating frequency of 1Hz, and a stroke of 10mm. The test lasted 30 minutes and resulted in an average friction coefficient of 0.43.

[0048] Example 4

[0049] The prepared lithium-based grease was placed in an ATR sample chamber to evaluate its friction performance. A 6mm alumina ball was used as the grinding head, with a load of 1N, a reciprocating frequency of 1Hz, and a stroke of 10mm. The friction test was conducted at room temperature for 30 minutes. The average friction coefficient was 0.37.

[0050] Example 5

[0051] The prepared lithium-based grease was placed in an ATR sample chamber to evaluate its friction performance. A 6mm titanium alloy ball was used as the grinding head, with a load of 1N, a reciprocating frequency of 1Hz, and a stroke of 10mm. The friction test was conducted at room temperature for 30 minutes, and the average friction coefficient was 0.45.

[0052] Example 6

[0053] The prepared lithium-based grease was placed in an ATR sample chamber to evaluate its friction performance. A 6mm silicon nitride ceramic ball was used as the grinding head. The test was conducted at room temperature with a load of 1N, a reciprocating frequency of 1Hz, and a stroke of 10mm. The test lasted 30 minutes and resulted in an average friction coefficient of 0.54.

[0054] Example 7

[0055] The prepared lithium-based grease was placed in an ATR sample tank to evaluate its friction performance. A GCr15 6mm steel ball was used as the grinding head, with a load of 5N, a reciprocating frequency of 1Hz, a stroke of 10mm, and friction tests conducted at room temperature for 30 minutes. The average friction coefficient was 0.12.

[0056] Example 8

[0057] The prepared lithium-based grease was placed in an ATR sample tank to evaluate its friction performance. A GCr15 6mm steel ball was used as the grinding head, with a load of 10N, a reciprocating frequency of 1Hz, a stroke of 10mm, and friction tests conducted at room temperature for 30 minutes. The average friction coefficient was 0.18.

[0058] Example 9

[0059] The prepared lithium-based grease was placed in an ATR sample tank to evaluate its friction performance. A GCr15 6mm steel ball was used as the grinding head, with a load of 5N, a reciprocating frequency of 3Hz, a stroke of 10mm, and friction tests conducted at room temperature for 30 minutes. The average friction coefficient was 0.13.

[0060] Example 10

[0061] The prepared lithium-based grease was placed in an ATR sample tank to evaluate its friction performance. A GCr15 6mm steel ball was used as the grinding head, with a load of 5N, a reciprocating frequency of 7Hz, a stroke of 10mm, and friction tests conducted at room temperature for 30 minutes. The average friction coefficient was 0.16.

[0062] Example 11

[0063] The prepared lithium-based grease was placed in an ATR sample tank to evaluate its friction performance. A GCr15 6mm steel ball was used as the grinding head, with a load of 5N, a reciprocating frequency of 10Hz, a stroke of 10mm, and friction tests conducted at room temperature for 30 minutes. The average friction coefficient was 0.22.

[0064] The embodiments described above provide a detailed description of the technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements and equivalent substitutions made within the scope of the principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A tribochemical in-situ characterization device, characterized in that: The device comprises an ATR support, an ATR crystal and a heating module for a Fourier transform infrared spectrometer, wherein a sample slot is provided inside the ATR support, an optical path channel connected to the bottom of the sample slot is provided inside the ATR support, the ATR crystal is installed in the optical path channel, the heating module is arranged on the lower end surface of the ATR crystal, and the tribochemical in-situ characterization device further comprises a mechanical friction device arranged in the sample slot and above the ATR crystal; The mechanical friction device comprises a slide rail fixed on the top of the ATR support frame, an adapter block slidably arranged on the slide rail, and a grinding head detachably fixed to the lower end of the adapter block, wherein the material, surface roughness and hardness parameters of the grinding head are set according to the experimental requirements; a control system is provided on the adapter block, and the control system controls the pressure, movement mode and grinding speed of the grinding head on the surface of the ATR crystal by controlling the adapter block, and collects the friction coefficient and wear rate data of the sample material; During the test, the test sample was placed in the ATR sample slot and monitored in real time on-site using a Fourier transform infrared spectrometer. The time origin was set when the mechanical friction device started running, and the pressure, movement mode and grinding speed were set according to the experimental needs. The changes in the physical and chemical properties of the sample during the friction process were judged in real time based on the infrared spectrum and the friction coefficient and wear rate data collected by the control system, and the damage and failure time of the sample material were further judged to evaluate the service life of the sample material.

2. The tribochemical reaction in-situ characterization device according to claim 1, characterized in that: The end face of the grinding head facing the ATR crystal is circular, elliptical or polygonal.

3. The tribochemical reaction in-situ characterization device according to claim 1, characterized in that: The grinding head is made of stainless steel, hard alloy, copper alloy, aluminum alloy, titanium alloy, ceramic or diamond.

4. The tribochemical reaction in-situ characterization device according to claim 1, characterized in that: The material of the ATR crystal is diamond, silicon, germanium, zinc selenide or single crystal aluminum oxide.

5. The tribochemical reaction in-situ characterization device according to claim 1, characterized in that: The sample slot has a width of 1 mm to 20 mm and a length of 1 cm to 10 cm; The width of the end face of the grinding head facing the ATR crystal is smaller than the width of the sample slot, and the length of the end face is smaller than the length of the sample slot.

6. The tribochemical reaction in-situ characterization device according to claim 1, characterized in that: The control system regulates the unidirectional friction or bidirectional reciprocating friction of the grinding head by controlling the adapter block, the friction speed range is 0.01mm / s-1000mm / s, and the maximum friction stroke is the length of the sample slot.

7. The tribochemical reaction in-situ characterization device according to claim 1, characterized in that: The heating module is used to heat the sample in the sample tank, and the heating temperature range in the sample tank is 0-200°C.

8. The tribochemical reaction in-situ characterization device according to claim 1, characterized in that: The mechanical friction device also includes grease-pulling plates, which are arranged on both sides of the movement direction of the grinding head. The position of the grease-pulling plates is controlled by a control system so that the grease-pulling plates behind the grinding head are always located in the groove and work, and the grease squeezed to both sides of the sample groove by the grinding head is pushed back to the middle position to avoid the grease accumulating on both sides of the sample groove during the test and causing the grinding head to grind in vain.

9. A method for detecting grease indicators, characterized in that: The infrared spectrometer used is equipped with the tribochemical reaction in-situ characterization device described in any one of claims 1 to 8, and the specific detection process is as follows: Apply the grease to be tested to the sample slot on the upper surface of the ATR crystal; The working temperature of the grease is set by the heating module, and the control system rubs the grease on the surface of the ATR crystal by adjusting the pressure, movement mode and grinding speed of the grinding head on the surface of the ATR crystal. At the same time, the control system uploads the pressure, movement mode and grinding speed data to the computer in real time; During the friction process of the grease, the infrared light emitted by the infrared spectrometer passes through the optical path. The grease on the upper surface of the ATR crystal is irradiated by infrared spectroscopy, and the changes in the absorption peaks of the functional groups of the grease during the friction process are monitored in real time to determine the chemical reactions that occur in the grease during the friction process. The control system monitors the changes in the friction coefficient and wear rate data on the grease interface, and uses infrared spectroscopy to determine the changes in the grease's service performance and the grease's failure time in real time.

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