| With the rapid development of social economy, the vast ocean space and rich marine resources have started to enter people's vision. The ocean which rich in biological resources, energy resources and ocean energy resources is a vast treasure trove of resources. The development of marine resources depends on the research and development of ocean proprietary material, and the friction and wear in harsh marine environment is one of key issues restricting the application of marine materials and the promotion of marine equipment, so this paper will study on the tribocorrosion behavior of 316 L stainless steel and 2205 duplex steel commonly used in seawater,provide a theoretical basis for selection marine materials in tribocorrosion environment.The tribocorrosion tests of 316 L are conducted under both tribocorrosion condition and pure mechanical wear condition(cathodic protection). Using the test methods of XRD, metallurgical, electrochemical corrosion tests and wear synergies analyze that sliding influence on corrosion and wear properties of stainless steel from microscopic structural phase. The results are as follows:(1) A decrease in wear values for 316 L samples under high load condition in comparison with those under low load is observed. It shows the information of martensite during sliding process by XRD, microstructure analysis, and the mass fraction of martensite is about 70% or more; It founds that seawater corrosion hamper martensite transformation in comparison with pure mechanical wear conditions.(2) In order to study the microstructure transformation influence on the corrosion behaviors of AISI 316 L in artificial seawater, the potentiodynamic polarization curves and Electrochemical impedance spectroscopy(EIS) are conducted to measure the electrochemical behavious of the worn surface. The results show that the information of martensite affect the surface characteristic and stability of passive film, resulting in the decrease of corrosion resistance of stainless steel. The electrochemical impedance(EIS) analysis also obtained similar results, generating microscopic galvanic couplings because of the presence of ??- martensite and austenite within wear tracks change the electrochemical behavior of stainless steel.(3) The results show that the sea corrosion accelerates the loss of material, and suitable cathodic protection will affect the tribocorrosion behavior of stainless steel and reduces the wear rates; the tribocorrosion in seawater lead to microstructure evolution of stainless steel, and seawater corrosion hamper martensite transformation.and reduce the corrosion resistance of stainless steel.(4) This paper will study on the tribocorrosion behavior of 2205 duplex steel under tribocorrosion conditions and pure mechanical wear conditions. The results showed that the wear rate is smaller under high load condition. Sliding in seawater make the formation of ? phase, dislocation and lattice irregularities, and improve the wear resistance of dual phase steel. 2205 duplex steel has less wear rate and better wear resistance compared with 316 L.(5) The electrochemical properties of wear surfaces is tested by using electrochemical workstation. It found that corrosion potential decreases and the current density increases. The electrochemical impedance(EIS) analysis also obtained that resistance value decreases, and weak the corrosion resistance of duplex steel. The information of ? phase reduce the content of Cr and Mo elements around the ferritic and austenitic, so that make it easier for corrosion in seawater and easy to the formation of pitting in these regions.(6) The contribution of mechanical wear is prevailing in total wear-corrosion degradation, accounting for about 80% to 90%. The materials loss is smaller compared with 316 L stainless steel. In summary, it concluded that 2205 duplex steel having superior abrasion performance in the marine environment, more suitable for use in tribocorrosion environments. |
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