In this study, the effect of various normal loads on the dry sliding wear, microstructure evolution, and resulting corrosion behavior of martensitic AISI 420 were investigated. The results revealed adhesion-dominated wear with material transfer and particles, leading to the formation of a lamellar microstructure containing delamination and pores around partly broken carbides. The microstructure evolution resulted in a significant decrease of the local corrosion resistance in 0.15 M NaCl solution, which was accompanied by a high concentration of corrosion sites within the worn areas. Dissolution inside the wear tracks was concentrated on the deformed microstructure. As the normal load increased, the effects of the wear intensified, further reducing the local corrosion resistance.

In the present study, the influence of the electrochemical potential on the tribocorrosion behavior of X20Cr13 in 0.15 molar NaCl-solution was investigated with the aid of a universal-tribometer under potentiostatic control. The resulting material loss was determined through laser confocal microscopy, while the morphology of the wear tracks and the deformation of the material structure near the surface were observed using light and scanning electron microscopy. The results showed a clear dependence of the material loss and the wear mechanisms from the applied potential. Within the cathodic region, a small amount of the material degradation could be attributed to a strong adhesion and resulting strain hardening as a consequence of an electrochemical weakening and mechanical destruction of the passive layer. The maximum of wear during polarization at the free corrosion potential under friction was explained by galvanic coupling between the wear track and the passive surface near the stability threshold between Fe2+-Ion and Fe2O3 development. Through increasing Polarization onto the free corrosion potential in the absence of friction and into the passive region, a decrease in material loss could be observed which is presumably attributed to the stable passive layer that inhibits electrochemical degradation and favors the formation of a grain refinement zone that slows down mechanical destruction.

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In this study, the effects of cycle dependent wear on the consecutive corrosion behaviour of AISI 420 in 0.15 M NaCl solution were investigated to determine the influence of the tribological microstructure alteration on the electrochemical behaviour. The results revealed adhesion dominated wear at low cycle counts that led to the formation of a lamellar microstructure with delamination and enlarged Cr-depleted areas, resulting in a significant decline in pitting corrosion resistance. As the number of cycles increased, a transition of the wear mechanisms towards abrasion was observed. The progressive deformation allowed strong grain refinement and homogenization of the microstructure, which led to a significant increase in the pitting corrosion potential.