Tribological and corrosion behaviour of medical grade 316LVM steel by low temperature hybrid gaseous nitriding and carburizing

This study approached a low temperature hybrid gaseous nitriding and carburizing at varying temperature and gas composition to develop S-phase layer on 316LVM steel. The hybrid gaseous treatment at 475 degrees C and 10 % CH4 developed a distinct S-phase layer that is harder (1444 +/- 32 HV0.025) than untreated surface. The S-phase layers are effective in reducing specific wear rates by 67 % to 1.19 +/- 0.05 x 10-3 mm3/Nm, coefficients of friction by 26 % to 0.49 +/- 0.02, and corrosion rate by 23 % to 6.02 +/- 0.32 mu m/y. Both untreated and treated surfaces had dominant abrasive wear mechanisms but on treated surface spalling holes were observed. This research highlights low-temperature hybrid gaseous nitriding and carburizing is promising for improving 316 LVM steel surface for orthopedic.