CN-121977996-A - Accelerated test method for simulating corrosion condition of part in marine atmosphere environment

CN121977996ACN 121977996 ACN121977996 ACN 121977996ACN-121977996-A

Abstract

The invention provides an accelerated test method for simulating corrosion conditions of parts in a marine atmosphere environment, which comprises the steps of placing test parts in the simulated environment for periodic corrosion tests, wherein the periodic corrosion tests comprise a wet heat test, a dry test and a salt spray test, the wet heat test and the salt spray test are alternately carried out, and the dry test is arranged after each wet heat test and after each salt spray test. Thus, a dry-wet alternating periodic corrosion test is introduced, and a plurality of stages of wetting, electrochemical corrosion, drying crystallization and the like existing in the natural corrosion process are more truly simulated. The wet-heat test and the salt spray test simulate the corrosion environment of high humidity and salt deposition, and the key drying test promotes the conversion of corrosion products and the diffusion of oxygen, which is more consistent with the formation process of a corrosion layer in the natural environment, so that the corrosion mechanism and the microscopic morphology of the corrosion products generated by the acceleration test are better consistent with the corrosion condition in the real natural environment, and the accuracy of the test result is improved.

Inventors

ZHANG YUANBIN
CUI SHAOJIE
LI CHUNGUO
SUN DONG
CUI ZHIGUO

Assignees

中车青岛四方机车车辆股份有限公司

Dates

Publication Date: 20260505
Application Date: 20260309

Claims (10)

1. An accelerated test method for simulating corrosion of a part in an ocean atmosphere, comprising: placing the test part in a simulation environment, and performing a periodic corrosion test; The periodic corrosion test comprises a wet heat test, a dry test and a salt spray test, wherein the wet heat test and the salt spray test are alternately carried out, and the dry test is arranged after each wet heat test and after each salt spray test.
2. The method for accelerated testing of corrosion conditions of a part in a marine atmosphere of claim 1, further comprising, prior to said periodically performing the corrosion test: determining the test conditions of the wet and hot test, the test conditions of the salt spray test and the test conditions of the drying test according to the target service environment corresponding to the test part; The test conditions of the wet heat test at least comprise a wet heat test temperature, a wet heat test humidity and a wet heat test time, the test conditions of the salt spray test at least comprise a salt spray test temperature, a salt spray settlement amount and a salt spray test time, and the test conditions of the dry test at least comprise a dry test temperature, a dry test humidity and a dry test time.
3. The accelerated test method for simulating the corrosion conditions of a part in a marine atmosphere according to claim 2, wherein the determining the test conditions of the wet heat test, the salt spray test and the dry test according to the target service environment corresponding to the test part comprises: Determining the damp-heat test temperature and the damp-heat test humidity according to the annual average temperature and the annual average humidity of the target service environment; Determining the damp-heat test time, the salt spray test time and the drying test time according to a temperature and humidity database, a test time calculation model, the damp-heat test temperature and the damp-heat test humidity of the target service environment, wherein the temperature and humidity database of the target service environment is included in N years of the target service environment, and actual temperature data and actual humidity data are acquired according to a preset time interval, wherein N is a positive integer.
4. The method of accelerated testing of corrosion conditions of a part in a marine atmosphere of claim 3, wherein the test time calculation model comprises a first calculation model, the first calculation model being: ; The method comprises the steps of (a) converting the corrosion speed of a salt spray test to the corrosion speed of a damp heat test, T Salt fog , T Damp-heat type , k, E a , R, T k , T Test , RH k , RH Test and RH Test , wherein alpha is the conversion rate of the corrosion speed of the salt spray test to the corrosion speed of the damp heat test, T Salt fog is the total time of the salt spray test, T Damp-heat type is the total time of the damp heat test, k is the acquisition time corresponding to the actual temperature data and the actual humidity data in a temperature and humidity database of a target service environment, and the adjacent two acquisition times are spaced by 1 hour, E a is the activation energy corresponding to the material of a test part, R is an ideal gas constant, T k is the actual temperature data of the k time in the temperature database of the target service environment, T Test is the damp heat test temperature, RH k is the actual humidity data of the temperature database of the target service environment, RH Test is the humidity of the damp heat test, and n is the humidity coefficient.
5. The method of accelerated testing of a simulated part for corrosion in an ocean atmospheric environment of claim 4, wherein the test time calculation model further comprises a second calculation model, the second calculation model being: ; Wherein t Drying is the total time of the drying test in hours, and t Target object is the total test time required for testing the corrosion condition to reach the corrosion condition in N years of the target service environment in hours.
6. The accelerated test method for simulating corrosion conditions of parts in a marine atmosphere according to any one of claims 1 to 5, wherein the wet heat test temperature is 37 to 43 ℃, the wet heat test humidity is 85 to 95%, and the wet heat test time is 7 to 10 hours per cycle; the salt spray test temperature is 37-43 ℃, the salt spray settlement amount is 1.0-1.5 milliliters per square millimeter per hour, the salt spray test time of each period is 7-12 hours, the spray liquid adopted in the salt spray test is a salt solution, and the mass fraction of the salt solution is 4.55-5.5 wt%; The drying test temperature is 47-53 ℃, and the drying test humidity is 20% -30%.
7. The method of accelerated testing of corrosion conditions of a part in a marine atmosphere according to any of claims 1-5, wherein the number of cycles of the periodic corrosion test is greater than or equal to 15.
8. The method for accelerated testing of corrosion conditions of a simulated part in a marine atmosphere according to any of claims 1-5, further comprising, prior to placing the tested part in the simulated environment: Removing impurities on the surface of the test part, wherein the impurities comprise greasy dirt or grease; Drying the test part; The test parts were weighed.
9. The method for accelerated testing of corrosion conditions of a part in a marine atmosphere according to any of claims 1-5, further comprising, after said performing of the periodic corrosion test: Detecting and analyzing the surface corrosion morphology of the test part subjected to the periodic corrosion test; post-processing the test part subjected to the periodic corrosion test; And detecting and analyzing the corrosion rate of the test part subjected to the post-treatment.
10. The method of accelerated testing of corrosion conditions of a part in a marine atmosphere according to claim 9, wherein said post-treating the test part subjected to the periodic corrosion test comprises: removing corrosion products on the surface of the test part subjected to the periodic corrosion test; flushing the test part after the corrosion products are removed; and drying the washed test part.

Description

Accelerated test method for simulating corrosion condition of part in marine atmosphere environment Technical Field The invention relates to the technical field of simulation tests, and provides an acceleration test method for simulating corrosion conditions of parts in a marine atmosphere environment. Background The high-strength fastening connecting piece is a key component of a high-speed train and is used for connecting a core structure of a train body and a carriage, and the performance of the high-strength fastening connecting piece is directly related to the safety and the stability of the high-speed running of the train. These fastening connectors can be exposed to severe corrosion problems when in service in high-salt, high-humidity marine atmospheric environments such as coastal areas. The salt and the moisture in the ocean atmosphere can erode the metal material, so that the service life of the fastening connecting piece can be shortened, and potential safety hazards such as structural strength reduction, connection looseness and the like are more likely to be caused, and therefore, the accurate assessment of the corrosion condition of the fastening connecting piece is very important. Currently, corrosion evaluation mainly depends on natural environment exposure tests and indoor accelerated corrosion tests. Although the natural environment exposure test can reflect the corrosion behavior of the fastening connection piece most truly, the test period is very long, usually years or even decades are required, the cost is high, and the efficiency requirements of rapid research and development of new materials and engineering application cannot be met. While in-house accelerated corrosion tests, such as neutral salt spray tests, accelerate the corrosion process by creating a constant high temperature, high humidity and high salt spray environment in the test chamber. But this single environment of constant wetting is severely inconsistent with the real natural environment. The corrosion mechanism and the corrosion product morphology generated by the continuous salt spray test are obviously different from those of the real natural environment, the correlation between the test result and the real natural environment is poor, the method can be only used for qualitative comparison of the corrosion resistance of materials, and the service life of the parts is difficult to be accurately predicted. Therefore, how to solve the problem of poor accuracy of results when the corrosion condition of the part in the marine atmosphere environment is simulated by using the accelerated corrosion test in the related art is an important technical problem to be solved by the person skilled in the art. Disclosure of Invention The embodiment of the invention provides an accelerated test method for simulating the corrosion condition of a part in an ocean atmosphere environment, which is used for solving the defect of poor result accuracy when the corrosion condition of the part in the ocean atmosphere environment is simulated by utilizing an accelerated corrosion test in the related technology, improving the test accuracy and being beneficial to realizing the accurate prediction of the service life of the part. The invention provides an acceleration test method for simulating corrosion conditions of parts in a marine atmosphere environment, which comprises the following steps: placing the test part in a simulation environment, and performing a periodic corrosion test; The periodic corrosion test comprises a wet heat test, a dry test and a salt spray test, wherein the wet heat test and the salt spray test are alternately carried out, and the dry test is arranged after each wet heat test and after each salt spray test. According to the accelerated test method for simulating the corrosion condition of the part in the marine atmosphere environment, which is provided by the invention, before the periodic corrosion test, the accelerated test method further comprises the following steps: determining the test conditions of the wet and hot test, the test conditions of the salt spray test and the test conditions of the drying test according to the target service environment corresponding to the test part; The test conditions of the wet heat test at least comprise a wet heat test temperature, a wet heat test humidity and a wet heat test time, the test conditions of the salt spray test at least comprise a salt spray test temperature, a salt spray settlement amount and a salt spray test time, and the test conditions of the dry test at least comprise a dry test temperature, a dry test humidity and a dry test time. According to the accelerated test method for simulating the corrosion condition of the part in the marine atmosphere environment, the test conditions of the damp-heat test, the salt spray test and the drying test are determined according to the target service environment corresponding to the test part, and the accelerated test me