Method and device for testing abrasion and corrosion of metal component in marine atmosphere thin liquid film environment

Abstract

The invention provides an experimental method and device for abrasion and corrosion of a metal component in a marine atmosphere thin liquid film environment, and belongs to the field of abrasion and corrosion failure detection. According to the method, the abrasion increment caused by the corrosion effect can be finally obtained. The device comprises a thin liquid film forming module, a thin liquid film measuring module, a friction abrasion module and an electrochemical in-situ monitoring module. During an experiment, firstly, a metal component is processed into a metal component in a target form, a grinding head, a to-be-tested wear sample and the thin liquid film forming module are assembled on the friction wear module, environmental parameters are determined through the thin liquid film measuring module, finally, the electrochemical in-situ monitoring module is connected, and the friction wear module is started for cooperative operation. The experimental method and device are particularly suitable for testing the abrasion and corrosion performance of the metal component in the marine atmospheric environment, the shape, size and contact mode of the metal component can be designed according to the actual friction state, and the experimental method and device have the advantages of being high in friction scene reduction degree and high in simulation authenticity.

Description

Technical Field

[0001] This invention relates to the field of wear and corrosion failure detection, specifically to an experimental method and apparatus for wear and corrosion testing of metal components in a marine atmospheric thin liquid film environment. Background Technology

[0002] In the hot and humid marine atmosphere, materials used in ships and marine engineering equipment not only corrode due to the chemical and electrochemical effects of the environmental medium, resulting in thinning, cracking, and other performance degradation, but their moving metal components also experience material wear due to relative friction, leading to material migration and surface damage. More seriously, under actual operating conditions, mechanical wear and environmental corrosion often coexist, and these two processes are not simply superimposed but rather produce an interactive and synergistic effect—wear corrosion. This coupling effect can accelerate the failure rate of materials by orders of magnitude. Wear corrosion damage directly affects the vibration and motion accuracy of metal components, and can even trigger sudden functional failures. To address this challenge, there is an urgent need to develop specialized testing devices and methods that can realistically reproduce the thin liquid film environment of the atmosphere and accurately evaluate the wear corrosion behavior of metal components under such conditions.

[0003] Currently, although relatively complete test equipment and evaluation methods exist in the field of coupled wear and corrosion damage detection of materials, the construction of dedicated simulation devices and test methods for wear and corrosion between metal components under the specific environment of atmospheric thin liquid film are still weak links.

[0004] Chinese patent application CN115235929A discloses a friction and wear testing device and method for a corrosion simulation medium environment. It uses a salt spray generator, salt spray rubber hose, and salt spray nozzle to provide a corrosive medium to simulate a marine atmospheric environment, suitable for detecting and comparing the friction and wear corrosion performance of structural steel used in complex environments. However, this patent's friction and wear module only involves ball-disc friction between alumina, silicon carbide, and silicon nitride grinding balls and workpieces, without considering the actual friction conditions between metal components. Additionally, Chinese patent application CN120489929A ​​discloses a high / low temperature wear-corrosion coupled damage testing device and quantitative evaluation method. It uses a high / low temperature external circulation temperature controller and a temperature-controlled liquid circulation chamber to regulate temperature, achieving high-precision testing and quantitative analysis of wear and corrosion of metal-based materials in high and low temperature environments. However, this patent does not consider both marine atmospheric environment simulation and friction between metal components.

[0005] To date, existing technologies have enabled the evaluation of wear-corrosion coupled damage, but methods for detecting and evaluating wear-corrosion failures between metal components are still lacking. Therefore, in order to meet the need to reproduce the actual service conditions of metal components in the laboratory, it is necessary to study an experimental method and apparatus for wear-corrosion of metal components in a marine atmospheric thin liquid film environment. Summary of the Invention

[0006] To address the shortcomings of the prior art, the present invention aims to provide a test method and apparatus for wear and corrosion of metal components in a marine atmospheric thin liquid film environment. This method enables the evaluation of wear and corrosion failure of moving metal components in a high-humidity and hot marine atmospheric environment, and provides crucial and reliable data support for assessing the durability of metal components under harsh conditions such as marine atmosphere in a laboratory environment.

[0007] Specifically, on the one hand, the present invention provides a method for testing the wear and corrosion of metal components in a marine atmospheric thin liquid film environment, comprising the following steps: S1. Based on actual working conditions, the metal component is processed into a grinding head sample and a wear sample to be tested with the target size and shape. The working electrode is prepared using the wear sample to be tested. The working electrode is fixed in the working electrode tank of the electrolytic cell. A micrometer with a platinum needle is fixed directly above the working electrode. The micrometer is adjusted to move the platinum needle downward. When the tip of the platinum needle contacts the surface of the working electrode, the resistance value of the ohmmeter will change abruptly. At this time, the downward movement is stopped, and the scale value m1 of the micrometer is recorded. Then the platinum needle is moved upward and away from the surface of the working electrode. S2. Inject the corrosive solution medium into the electrolytic cell to form a thin liquid film on the surface of the working electrode. Move the platinum needle down again. When the tip of the platinum needle contacts the solution surface, the resistance value of the ohmmeter will change abruptly again. Record the micrometer scale value m2 at this time and calculate the thickness of the liquid film as m1-m2. S3. Install the grinding head sample into the sample clamping unit of the friction testing machine, assemble the electrolytic cell onto the worktable of the friction testing machine, control the grinding head sample to extend into the electrolytic cell through the friction testing machine, and adjust the initial friction position. S4. Install the counter electrode and reference electrode to form a complete three-electrode system and connect the three-electrode system to the electrochemical workstation. Set the friction load, frequency and time, and start the friction testing machine and electrochemical workstation simultaneously to begin the wear and corrosion failure test. S5. Conduct wear corrosion tests at open circuit potential. After the test, calculate the total volumetric loss V of the wear sample under test. T The calculation formula is: V T =SL; Where S is the cross-sectional area and L is the wear mark length; S6. Conduct a friction test under cathodic protection potential. After the test, calculate the volume loss V caused by pure wear using the calculation formula in step S5. W ; S7. Conduct potentiodynamic polarization tests, measure the polarization curves under static and triboelectric conditions, and obtain the static corrosion current density I and the triboelectric corrosion current density It. M I R for I and I M difference; Calculate the volume loss V caused by pure corrosion according to Faraday's law. C = ItM / nFρ and corrosion increment ΔV caused by wear C =I M tM / nFρ; Where t is the friction time; M is the molar mass of the metal; n is the charge transfer number; F is the Faraday constant; and ρ is the material density. S8. Obtain the wear increment caused by corrosion, calculated using the following formula: ΔV W = V T -V W -V C -ΔV C .

[0008] Preferably, in step S7, the static corrosion current density I and the triboelectric corrosion current density It are obtained by Tafel extrapolation. M .

[0009] Preferably, I R Used to quantify the synergistic accelerating effect of friction and corrosion, characterizing the degree to which friction accelerates corrosion.

[0010] Preferably, after the test in steps S5 and S6, a three-dimensional profilometer is used to observe the cross-sectional view of the wear mark on the sample, and the cross-sectional area and wear mark length are obtained based on the cross-sectional view.

[0011] Secondly, the present invention provides a marine atmospheric thin liquid film environment metal component wear and corrosion test device for the above-mentioned marine atmospheric thin liquid film environment metal component wear and corrosion test method, which includes a thin liquid film forming module, a thin liquid film measuring module, a friction and wear module, and an electrochemical in-situ monitoring module; wherein, the thin liquid film forming module is used to provide a corrosive medium for the friction and wear module, the thin liquid film testing module is used to determine the liquid film environment thickness parameters, the friction and wear module is used to realize friction reciprocating motion, and the electrochemical in-situ monitoring module is used for corrosion performance testing; The thin liquid film forming module includes an electrolytic cell and a corrosive solution medium; the corrosive solution medium is stored inside the electrolytic cell, and a working electrode tank for installing the working electrode is set in the middle of the electrolytic cell. The thin liquid film measurement module includes an ohmmeter, a micrometer screw gauge, and a comparison stage. The micrometer screw gauge is installed on the comparison stage, and the ohmmeter is used to monitor the circuit resistance in real time. The micrometer screw gauge moves from the sample surface to the liquid film surface through a platinum needle, and the thickness of the thin liquid film is directly obtained based on the scale difference. The friction and wear module includes a friction testing machine and a grinding head sample for simulating target metal components; the electrochemical in-situ monitoring module includes an electrochemical workstation and a three-electrode assembly. The electrochemical workstation has high current resolution and can achieve stable signal acquisition under mechanical motion interference conditions; the three-electrode system includes a working electrode, a counter electrode, and a reference electrode.

[0012] Preferably, the working electrode includes the wear sample to be tested, a wire, epoxy resin, and a PVC tube. The wire is connected to the back of the wear sample to be tested, and the wear sample to be tested is encapsulated and fixed in the PVC tube using epoxy resin. The counter electrode is made of an inert material, and the reference electrode is a miniature saturated calomel electrode, an Ag electrode, or an AgCl electrode.

[0013] Preferably, the micrometer has a platinum needle.

[0014] Preferably, the friction testing machine includes a sample clamping unit, a load unit, a control unit, a data acquisition and analysis unit, and a safety protection unit.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: The experimental method for wear and corrosion of metal components in a marine atmospheric thin liquid film environment provided by this invention has a wide-range testing capability that is adaptable to multiple scenarios. It effectively overcomes the core limitations of traditional testing methods, such as insufficient material compatibility, low accuracy of working condition reproduction, and single testing scenario. It provides a technical solution that is more in line with the actual application needs for the reliability assessment of metal components in the engineering field and can be applied in multiple scenarios.

[0016] The experimental method for wear and corrosion of metal components in a marine atmospheric thin liquid film environment provided by this invention can not only test the same type of metal components made of various commonly used engineering metal materials, but also meet the needs of heterogeneous pairing tests of metal components with different materials and properties. It covers typical material pairing scenarios of metal components in aerospace, marine engineering, shipbuilding, and marine oil and gas development, and solves the problems of poor adaptability of traditional test methods to heterogeneous metal pairing tests and easy instability of the test system.

[0017] The present invention provides a method and apparatus for testing the wear and corrosion of metal components in a marine atmospheric thin-film environment. On the one hand, it can accurately reproduce the key geometric parameters of the metal components; on the other hand, it can precisely simulate the actual contact patterns of the metal components. Furthermore, it allows for flexible adjustment of key test parameters such as load magnitude, friction frequency, and stroke distance according to specific testing needs, constructing highly customized single or composite working condition simulation schemes. This design completely solves the shortcomings of fixed working condition parameters and rigid simulation scenarios in traditional testing methods, making the test environment highly consistent with the harsh working conditions of actual service of metal components, such as marine atmosphere, high salt spray, humid and hot conditions, and alternating salt spray and wet / dry conditions.

[0018] The present invention provides a method and apparatus for testing the wear and corrosion of metal components in a marine atmospheric thin-film environment. This method enables the precise acquisition of key quantitative data on wear rate, corrosion depth, surface morphology evolution, and mechanical property degradation of metal components under complex and harsh operating conditions within a controlled laboratory environment. These data provide highly reliable core evidence for the durability assessment and service life prediction of metal components, and offer solid technical support for the research and development and engineering applications of related products. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the experimental method for wear and corrosion of metal components in a marine atmospheric thin liquid film environment according to the present invention; Figure 2 This is a schematic diagram of the experimental apparatus for wear and corrosion of metal components in a marine atmospheric thin liquid film environment according to the present invention. Figure 3 This is a schematic diagram of the grinding head sample in Embodiment 1 of the present invention; Figure 4 This is a bar chart of the volume loss components after wear and corrosion of the 1Cr15Ni4Mo3N-1Cr15Ni4Mo3N component in Embodiment 1 of the present invention. Figure 5 This is a bar chart showing the volume loss components of the 1Cr17Ni2-316L component after wear and corrosion in Embodiment 2 of the present invention.

[0020] The main reference numerals are as follows: 1. Corrosive solution medium; 2. Grinding head sample; 3. Friction testing machine; 4. Micrometer; 5. Platinum needle; 6. Ohmmeter; 7. Electrochemical workstation; 8. Counter electrode; 9. Reference electrode; 10. Working electrode; 11. Electrolytic cell; 12. Storage tank; 13. Bolt; 14. Comparison test platform; 15. PVC pipe; 16. Epoxy resin; 17. Wear sample to be tested. Detailed Implementation

[0021] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0022] Specifically, on the one hand, the present invention provides an experimental apparatus for wear and corrosion testing of metal components in a marine atmospheric thin liquid film environment, such as... Figure 2 As shown, it includes a thin liquid film forming module, a thin liquid film measurement module, a friction and wear module, and an electrochemical in-situ monitoring module; wherein, the thin liquid film forming module is used to provide a corrosive medium for the friction and wear module, the thin liquid film testing module is used to determine the liquid film environmental thickness parameters, the friction and wear module is used to realize frictional reciprocating motion, and the electrochemical in-situ monitoring module is used for corrosion performance testing.

[0023] The thin film forming module includes an electrolytic cell 11 and a corrosive solution medium 1; the corrosive solution medium 1 is stored inside the electrolytic cell 11, and a working electrode slot for mounting the working electrode is provided in the middle of the electrolytic cell 11. Storage tanks 12 are provided on both sides of the electrolytic cell 11.

[0024] The thin liquid film measurement module includes an ohmmeter 6, a micrometer screw gauge 4, and a comparison stage 14. The micrometer screw gauge 4 is mounted on the comparison stage, and the ohmmeter 6 is used to monitor the circuit resistance in real time. The micrometer screw gauge 4 retracts from the sample surface to the liquid film surface via a platinum needle 5, and the thickness of the thin liquid film is directly obtained based on the scale difference. The micrometer screw gauge 4 has a platinum needle 5. The comparison stage 14 is a marble comparison stage.

[0025] The friction and wear module includes a friction testing machine and a grinding head sample for simulating target metal components. The friction testing machine includes a sample clamping unit, a load unit, a control unit, a data acquisition and analysis unit, and a safety protection unit.

[0026] The electrochemical in-situ monitoring module includes an electrochemical workstation and a three-electrode assembly. The electrochemical workstation features high current resolution and can achieve stable signal acquisition under mechanical motion interference conditions. The three-electrode system includes a working electrode, a counter electrode, and a reference electrode. The working electrode consists of the wear sample to be tested (17), a wire, epoxy resin (16), and a PVC tube (15). The wire is connected to the back of the wear sample and then encapsulated and fixed inside the PVC tube (15) using epoxy resin (16). The counter electrode is made of an inert material, and the reference electrode is a miniature saturated calomel electrode, an Ag electrode, or an AgCl electrode.

[0027] Secondly, this invention provides a method for testing the wear and corrosion of metal components in a marine atmospheric thin liquid film environment, such as... Figure 1 As shown, it includes the following steps: S1. Based on actual working conditions, the metal component is processed into a grinding head sample and a wear sample to be tested with the target size and shape. The wear sample to be tested is placed in a PVC pipe and cured with epoxy resin as a working electrode. The working electrode is fixed in the working electrode tank of the electrolytic cell. A micrometer with a platinum needle is fixed directly above the working electrode. The micrometer is adjusted to move the platinum needle downward. When the tip of the platinum needle contacts the surface of the working electrode, the resistance value displayed by the ohmmeter will change abruptly, that is, jump from infinity to a certain finite value. Stop moving downward and record the micrometer scale value m1 of the number of times. Then move the platinum needle upward and away from the electrode surface.

[0028] S2. Inject a corrosive solution medium into the electrolytic cell to form a thin liquid film on the surface of the working electrode. Move the platinum needle down again. When the tip of the platinum needle contacts the solution surface, the resistance value displayed on the ohmmeter will change abruptly, that is, jump from infinity to a certain finite value. Record the micrometer scale value m2 at this time and calculate the thickness of the liquid film as m1-m2.

[0029] S3. Install the grinding head sample into the sample clamping unit, assemble the electrolytic cell onto the friction platform, control the grinding head sample to extend into the electrolytic cell through the friction testing machine, and adjust the initial friction position.

[0030] S4. Install the counter electrode and reference electrode. The counter electrode, reference electrode, and working electrode form a complete three-electrode system. Connect the three-electrode system to the electrochemical workstation. Set the parameters of the friction testing machine, such as friction load, frequency, and time. Start the friction testing machine and electrochemical workstation simultaneously to begin the wear and corrosion failure test.

[0031] S5. Conduct wear corrosion tests under open-circuit potential. After the test, use a three-dimensional profilometer to observe the cross-sectional view of the wear track on the test sample, and obtain the cross-sectional area and wear track length from the cross-sectional view. Calculate the total volumetric loss V of the grinding head sample. T The calculation formula is: V T = SL.

[0032] Where S is the cross-sectional area and L is the wear mark length.

[0033] S6. Conduct a friction test under cathodic protection potential, and calculate the volume loss V of the test wear sample caused by pure wear according to the calculation formula in step S5. W .

[0034] S7. Conduct potentiodynamic polarization tests to obtain polarization curves under static and frictional conditions, and use the Tafel extrapolation method to obtain the static corrosion current density I and the frictional corrosion current density If. M I R for I and I M The difference. Among them, I R Used to quantify the synergistic accelerating effect of friction and corrosion, characterizing the degree to which friction accelerates corrosion.

[0035] Based on Faraday's law, calculate the volume loss V caused by pure corrosion of the wear sample under test. C = ItM / nFρ and corrosion increment ΔV caused by wear C =I M tM / nFρ.

[0036] Where t is the friction time; M is the molar mass of the metal; n is the charge transfer number; F is the Faraday constant; and ρ is the material density.

[0037] S8. Obtain the wear increment caused by corrosion, calculated using the following formula: ΔV W = V T -V W -V C -ΔVC . Specific Implementation Example 1 This embodiment uses the present invention to conduct wear and corrosion tests on 1Cr15Ni4Mo3N-1Cr15Ni4Mo3N components in a marine atmospheric environment.

[0039] Specifically, this embodiment provides an experimental apparatus for the wear and corrosion of metal components in a marine atmospheric thin liquid film environment, including a thin liquid film formation module, a thin liquid film measurement module, a friction and wear module, and an electrochemical in-situ monitoring module. The thin liquid film formation module provides a corrosive medium for the friction and wear module, the thin liquid film testing module determines the liquid film environmental thickness parameters, the friction and wear module enables reciprocating frictional motion, and the electrochemical in-situ monitoring module is used for corrosion performance testing.

[0040] The thin liquid film forming module includes an electrolytic cell 11, a working electrode 10, and a corrosive solution medium 1. The electrolytic cell 11 is made of polymer materials such as polytetrafluoroethylene (PTFE) to avoid galvanic corrosion between it and the metal component. The central area is raised and has a pre-reserved working electrode groove, while storage tanks 12 on both sides are reserved to suppress liquid film evaporation. The lower surface is fixedly connected to the friction and wear module via bolts 13. The working electrode 10 is made of a wear sample 17 of the target metal component, wires, epoxy resin 16, and a PVC pipe 15. The wires are connected to the back of the wear sample 17, and then it is encapsulated and fixed within the PVC pipe 15 using epoxy resin 16. The corrosive solution 1 can be precisely prepared according to the ionic composition and concentration of the target real environment to simulate specific service conditions. Additionally, a heating wire and a temperature sensor can be used to control the temperature of the electrolyte solution.

[0041] The thin liquid film measurement module includes a high-precision ohmmeter 6, a micrometer 4 with an ultra-fine platinum needle 5, and a marble comparison stage 14. The high-precision ohmmeter 6 is used to monitor the circuit resistance in real time; the micrometer 4, through its platinum needle 5, retracts from the sample surface to the liquid film surface, directly obtaining the thickness of the thin liquid film based on the scale difference; the marble comparison stage 14 provides a stable mounting reference for the micrometer 4.

[0042] The friction and wear module includes a friction testing machine 3 and a grinding head 2 for simulating target metal components. The friction testing machine has a sample clamping system, a load system, a control system, a data acquisition and analysis system, and a safety protection system, capable of applying controllable reciprocating friction to the grinding head 2. The material, shape, and dimensions of the grinding head 2 are designed to reproduce the actual component; its non-friction parts are adapted to the clamping system of the testing machine and reliably fixed by bolts.

[0043] The electrochemical in-situ monitoring module includes an electrochemical workstation 7 and a three-electrode system. The electrochemical workstation 7 features high current resolution and can achieve stable signal acquisition under conditions of mechanical interference. The three-electrode system consists of a working electrode 10, a counter electrode 8, and a reference electrode 9. The working electrode 10 is made from the wear sample 17 of the target metal component, the counter electrode 8 uses inert materials such as platinum or graphite rods, and the reference electrode 9 uses a miniature saturated calomel electrode or an Ag / AgCl electrode.

[0044] The specific implementation steps are as follows: Sample preparation: 1Cr15Ni4Mo3N reference Figure 3 The grinding head sample was obtained by machining it into the target shape. The 1Cr15Ni4Mo3N was cut into a size of 10mm*10mm*3mm to obtain the wear sample to be tested. After connecting the wires to the back of the sample, it was cured with epoxy resin and embedded in a PVC tube to prepare the working electrode.

[0045] Thin film zero-point positioning: Fix the working electrode in the sample cell at the center of the electrolytic cell, and fix the micrometer with a platinum needle directly above the working electrode. Slowly adjust the micrometer to move the platinum needle down. When the tip of the platinum needle contacts the surface of the working electrode, the ohmmeter will show a resistance value that jumps from infinity to a certain finite value. At this point, stop moving down immediately and record the micrometer scale value of 5.565 mm. Then move the platinum needle up so that it is away from the electrode surface.

[0046] Thin film thickness measurement: A 3.5 wt.% NaCl corrosive solution was injected into the electrolytic cell, allowing it to overflow the 1Cr15Ni4Mo3N electrode and form a thin film on its surface. The platinum needle was then slowly lowered. When its tip contacted the solution surface, the ohmmeter reading showed the aforementioned step change in resistance. This value was recorded as 5.265 mm, and the film thickness was calculated to be 300 μm.

[0047] Install the friction test assembly: Install the grinding head sample into the clamping unit, assemble the electrolytic cell onto the friction platform, control the grinding head sample to extend into the electrolytic cell through the friction testing machine, and adjust the initial friction position.

[0048] Connect the three-electrode test circuit: Install the platinum counter electrode and the saturated calomel reference electrode to form a complete three-electrode system, and connect it to the electrochemical workstation using the shortest possible shielded cable.

[0049] Set parameters and start the test: Set the friction load to 10MPa, the friction frequency to 0.17Hz, and the friction time to 1h. Simultaneously start the friction testing machine and the electrochemical workstation to begin the wear and corrosion failure test.

[0050] like Figure 4As shown, the total volumetric wear corrosion loss in the tested 1Cr15Ni4Mo3N-1Cr15Ni4Mo3N sample under a marine thin-film environment, obtained using white light interferometry, was 2.07*10. -3 mm 3 The volume loss due to pure mechanical wear is 0.54*10. -3 mm 3 The corrosion current density measured from the static polarization curve was used to calculate, using Faraday's law, that the volume loss caused by pure corrosion was 0.0088 * 10⁻⁶. -3 mm 3 Based on the difference in corrosion current density between the static and dynamic polarization curves, the corrosion increment induced by wear is calculated to be 0.0088*10. -3 mm 3 The calculated wear increment caused by corrosion is 1.51 * 10⁻⁶. -3 mm 3 It is evident that the wear volume increase caused by corrosion accounts for over 70% of the total wear volume, highlighting the strong synergistic effect between corrosion and wear. The method of this invention can simulate the contact state of the same type of metal components under real-world working conditions, and is suitable for testing and studying their wear and corrosion behavior.

[0051] Example 2 This invention was used to conduct wear and corrosion tests on 1Cr17Ni2-316L components in marine atmospheric environments.

[0052] Sample preparation: 1Cr17Ni2 reference Figure 3 The grinding head sample was obtained by processing it into the target shape. The 316L was cut into 10mm*10mm*1mm size to obtain the wear sample to be tested. After connecting the wire to the back of the wear sample to be tested, it was cured with epoxy resin and embedded in a PVC tube to prepare the working electrode.

[0053] Thin film zero-point positioning: Fix the 316L wear sample to be tested as the working electrode in the sample cell in the center of the electrolytic cell. Fix a micrometer with a platinum needle directly above the working electrode. Slowly adjust the micrometer to move the platinum needle down. When the tip of the platinum needle contacts the surface of the working electrode, the resistance displayed on the ohmmeter will jump from infinity to a certain finite value. At this point, stop moving down immediately and record the micrometer scale value of 6.812 mm. Then move the platinum needle up to move it away from the electrode surface.

[0054] Thin film thickness measurement: A 3.5 wt.% NaCl corrosive solution is injected into the electrolytic cell, allowing it to overflow the working electrode and form a thin film on its surface. The platinum needle is then slowly lowered again. When its tip contacts the solution surface, the ohmmeter reading will show the aforementioned step change in resistance. This reading is recorded as 6.512 mm, and the film thickness is calculated to be 300 μm.

[0055] Install the friction test assembly: Install the grinding head sample into the clamping unit, assemble the electrolytic cell onto the friction platform, control the grinding head sample to extend into the electrolytic cell through the friction testing machine, and adjust the initial friction position.

[0056] Connect the three-electrode test circuit: Install the platinum counter electrode and the saturated calomel reference electrode to form a complete three-electrode system, and connect it to the electrochemical workstation using the shortest possible shielded cable.

[0057] Set parameters and start the test: Set the friction load to 10MPa, the friction frequency to 1Hz, and the friction time to 1h. Simultaneously start the friction testing machine and the electrochemical workstation to begin the wear and corrosion failure test.

[0058] After the test is completed, as follows Figure 5 As shown, the total volume loss of wear corrosion in the tested wear sample under marine thin liquid film conditions, obtained using a white light interferometer, is 4.10*10. -3 mm 3 The volumetric loss due to pure mechanical wear is 2.80*10. -3 mm 3 The corrosion current density measured from the static polarization curve was used to calculate, using Faraday's law, that the volume loss caused by pure corrosion was 0.0067 * 10⁻⁶. -3 mm 3 Based on the difference in corrosion current density between the static and dynamic polarization curves, the wear-induced corrosion increment is calculated to be 0.17 * 10⁻⁶. -3 mm 3 The corrosion-induced wear increment was calculated to be 1.13 * 10⁻⁶. -3 mm 3 The increase in volumetric loss due to corrosion caused by wear is two orders of magnitude higher than that of pure corrosion, and the increase in wear caused by corrosion accounts for 28% of the total loss. The method of this invention can simulate the contact state of dissimilar metal components under real working conditions and is suitable for testing and studying their wear and corrosion behavior.

[0059] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A test method for wear corrosion of metal components in a marine atmospheric thin liquid film environment, characterized in that: It includes the following steps: S1. Based on actual working conditions, the metal component is processed into a grinding head sample and a wear sample to be tested with the target size and shape. The working electrode is prepared using the wear sample to be tested. The working electrode is fixed in the working electrode tank of the electrolytic cell. A micrometer with a platinum needle is fixed directly above the working electrode. The micrometer is adjusted to move the platinum needle downward. When the tip of the platinum needle contacts the surface of the working electrode, the resistance value of the ohmmeter will change abruptly. At this time, the downward movement is stopped, and the scale value m1 of the micrometer is recorded. Then the platinum needle is moved upward and away from the surface of the working electrode. S2. Inject the corrosive solution medium into the electrolytic cell to form a thin liquid film on the surface of the working electrode. Move the platinum needle down again. When the tip of the platinum needle contacts the solution surface, the resistance value of the ohmmeter will change abruptly again. Record the micrometer scale value m2 at this time and calculate the thickness of the liquid film as m1-m2. S3. Install the grinding head sample into the sample clamping unit of the friction testing machine, assemble the electrolytic cell onto the worktable of the friction testing machine, control the grinding head sample to extend into the electrolytic cell through the friction testing machine, and adjust the initial friction position. S4. Install the counter electrode and reference electrode to form a complete three-electrode system and connect the three-electrode system to the electrochemical workstation. Set the friction load, frequency and time, and start the friction testing machine and electrochemical workstation simultaneously to begin the wear and corrosion failure test. S5. Conduct wear corrosion tests at open circuit potential. After the test, calculate the total volumetric loss V of the wear sample under test. T The calculation formula is: V T = SL; Where S is the cross-sectional area and L is the wear mark length; S6. Conduct a friction test under cathodic protection potential. After the test, calculate the volume loss V caused by pure wear using the calculation formula in step S5. W ; S7. Conduct potentiodynamic polarization tests, measure the polarization curves under static and triboelectric conditions, and obtain the static corrosion current density I and the triboelectric corrosion current density It. M I R for I and I M difference; Calculate the volume loss V caused by pure corrosion according to Faraday's law. C = ItM / nFρ and corrosion increment ΔV caused by wear C =I M tM / nFρ; Where t is the friction time; M is the molar mass of the metal; n is the charge transfer number; F is the Faraday constant; and ρ is the material density. S8. Obtain the wear increment caused by corrosion, calculated using the following formula: ΔV W = V T -V W -V C -ΔV C 。 2. The experimental method for wear corrosion of metal components in a marine atmospheric thin liquid film environment according to claim 1, characterized in that: In step S7, the static corrosion current density I and the triboelectric corrosion current density It are obtained using the Tafel extrapolation method. M .

3. The experimental method for wear corrosion of metal components in a marine atmospheric thin liquid film environment according to claim 1, characterized in that: IR is used to quantify the synergistic accelerating effect of friction and corrosion, characterizing the degree to which friction accelerates corrosion.

4. The experimental method for wear corrosion of metal components in a marine atmospheric thin liquid film environment according to claim 1, characterized in that: After the test in steps S5 and S6, a three-dimensional profilometer is used to observe the cross-sectional view of the wear track on the sample, and the cross-sectional area and wear track length are obtained based on the cross-sectional view.

5. A marine atmospheric thin-film environment metal component wear and corrosion test apparatus for the marine atmospheric thin-film environment metal component wear and corrosion test method described in claim 1, characterized in that: It includes a thin film forming module, a thin film measuring module, a friction and wear module, and an electrochemical in-situ monitoring module; wherein, the thin film forming module is used to provide a corrosive medium for the friction and wear module, the thin film measuring module is used to determine the thickness parameters of the liquid film environment, the friction and wear module is used to realize the friction reciprocating motion, and the electrochemical in-situ monitoring module is used for corrosion performance testing. The thin liquid film forming module includes an electrolytic cell and a corrosive solution medium; the corrosive solution medium is stored inside the electrolytic cell, and a working electrode tank for installing the working electrode is set in the middle of the electrolytic cell. The thin liquid film measurement module includes an ohmmeter, a micrometer screw gauge, and a comparison stage. The micrometer screw gauge is installed on the comparison stage, and the ohmmeter is used to monitor the circuit resistance in real time. The micrometer screw gauge moves from the sample surface to the liquid film surface through a platinum needle, and the thickness of the thin liquid film is directly obtained based on the scale difference. The friction and wear module includes a friction testing machine and a grinding head sample for simulating target metal components; the electrochemical in-situ monitoring module includes an electrochemical workstation and a three-electrode assembly. The electrochemical workstation has high current resolution and can achieve stable signal acquisition under mechanical motion interference conditions; the three-electrode system includes a working electrode, a counter electrode, and a reference electrode.

6. The experimental apparatus for wear and corrosion of metal components in a marine atmospheric thin liquid film environment according to claim 5, characterized in that: The working electrode includes the wear sample to be tested, a wire, epoxy resin, and a PVC tube. The wire is connected to the back of the wear sample to be tested, and the wear sample to be tested is encapsulated and fixed in the PVC tube using epoxy resin. The counter electrode is made of an inert material, and the reference electrode is a miniature saturated calomel electrode, an Ag electrode, or an AgCl electrode.

7. The experimental apparatus for wear and corrosion of metal components in a marine atmospheric thin liquid film environment according to claim 5, characterized in that: The micrometer has a platinum needle.

8. The experimental apparatus for wear and corrosion of metal components in a marine atmospheric thin liquid film environment according to claim 5, characterized in that: The friction testing machine includes a sample clamping unit, a load unit, a control unit, a data acquisition and analysis unit, and a safety protection unit.

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