Si_3N_4/NS315合金高温微动磨损特性研究

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

使用液压式高精度微动磨损试验机PLINT，以陶瓷球Si3N4为对磨副对国产690合金（国内牌号NS3l5）进行室温以及高温条件下的微动磨损试验，分析其三维摩擦特性曲线、摩擦系数、磨痕形貌。探究其磨损机理。实验结果表明：当位移为80-200um时，NS315合金处于滑移区；位移幅值对NS315合金的摩擦系数影响较小；法向载荷增加时，NS315合金摩擦系数升高；与室温相比，高温条件下NS315合金摩擦系数较高、磨损量较大，磨损情况严重；室温时，NS315合金磨损机理主要为磨粒磨损，而高温300℃时，其磨损机理主要表现为摩擦氧化以及剥层。

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 80-200um. 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℃.