TRIBOLOGICAL BEHAVIORS OF PLASMA NITRIDED AISI 316 LN TYPE STAINLESS STEEL IN AIR AND HIGH VACUUM ATMOSPHERE AT ROOM TEMPERATURE

摘要

In this work, tribological behaviors of the plasma nitrided AISI 316 LN type austenitic stainless steel specimens (both pins and rings) have been analyzed. The experiments have been conducted in high vacuum and in air atmosphere using Vacuum based high temperature Pin-on-disc tribometer. The tribological parameters such as friction coefficient and wear resistance have been analyzed by Origin graphs. The wear mechanisms involved have been identified by recording surface morphology on the wear track and pin surface through scanning electron microscope (SEM) and Optical profilometer. The self mating of AISI 316 LN type stainless steel (316LN) exhibits strong adhesion between the contact surfaces and severe surface damage both in air and in vacuum atmosphere. But, the self mating of Plasma Nitrided 316LN (CrN/CrN) reveals mild wear till the CrN coating peeled off from the pin surface. It has also been proved that Plasma Nitrided (CrN) layer on 316 LN ring was wear resistant layer when it is sliding against the untreated 316 LN pin in air and high vacuum atmosphere.