Tribological behaviour of a liquid nitrided precipitation-hardening (PH) stainless steel

A special type of precipitation-hardening stainless steel, of commercial name CORRAX, which is similar to DIN X3CrNiMoAl 13-8-2 W.Nr. 1.4534 is subjected to liquid nitriding (nitrocarburizing) in salt bath to enhance its wear behaviour. The tribological properties are evaluated using the standard pin-on-disk wear testing method with tungsten carbide counterface against three different steel conditions: nitrided, age-hardened (aged) and solution treated (delivery state). The variation of friction coefficient and wear volume were recorded as a function of applied normal load (5, 6, 8 and 10 N) and sliding distance for a constant running speed (0,6 m/s). Optical microscopy is also used to reveal the involved wear mechanisms.