A comparative study of low temperature plasma nitriding, carburising and nitrocarburising of AISI 410 martensitic stainless steel

摘要

Samples of an AISI410 martensitic stainless steel were plasma nitrided (PN), plasma carburised (PC) and plasma nitrocarburised (PCN) at a low temperature of 450°C for 20 h. General metallurgical characterisations were performed to compare the phase constituents, the chemical compositions, the microstructures and hardness of the untreated and various plasma treated surfaces. Pin on disc tests and polarisation corrosion tests were performed to evaluate the wear and corrosion properties of the plasma treated and untreated steel. The results showed that the low temperature plasma treated surfaces of 410 martensitic stainless steel were dominated with compounds of either nitrides (for PN), carbides (for PC) or a mixed structure of carbonitride and carbides (for PCN). Plasma nitriding and nitrocarburising significantly improved the surface hardness, wear resistance and corrosion resistance of the 410 martensitic stainless steel. However, plasma carburising under the present treatment condition only achieved a small increase in surface hardness and wear resistance. It had no clear influence on the polarisation corrosion properties of the 410 stainless steel.