Study on Fretting Characteristics of Si_3N_4/NS315 Alloy at High Temperature

The fretting wear behaviors of NS315 alloy were studied experimentally on a high precision hydraulic fretting wear machine at room temperature(25℃) and 300℃.This paper was designed to analyze the the friction characteristic curve,the fretting coefficients and the morphology of the worn surface,and the mechanism of fretting wear was discussed.Experimental results shows that the fretting wear of NS315 alloy is in a slip regime when the displacements are 80~200 μm.Friction Coefficient was not significantly related to the displacements but increased according to the normal load’s increment.Compared to the room temperature,NS315 Alloy got a higher friction coefficients,and the worn volume was larger at 300℃.The wear mechanism of the NS315 Alloy at 25℃ were mainly a combination of abrasive wear,delamination and oxidization wear,yet oxidization wear and delamination at 300℃.