Effect of Sliding Conditions on Micropitting Behaviour of AISI 304 Stainless Steel in Chloride Containing Solution

The tribo-electrochemical behaviour of AISI 304 austenitic stainless steel in 0.5M NaCl solution is investigated at an anodic potential of 70 mV(SCE) under controlled sliding and electrochemical conditions. It is found that at such an anodic potential where corrosion pits do not form without sliding, numerous micro-pits are found inside the sliding tracks under certain sliding conditions. There exists a critical combination of frequency, load and sliding duration for the development of the pits. The results are discussed considering the accumulation of mechanical damages induced by sliding and the competition between wear and pit growth during the process.