Self-lubrication of tribologically-induced oxidation during dry reciprocating sliding of aged Ti–Ni51.5 at％ alloy

• 作者: Rui YANG Wei MA Chunjian DUAN Song LI Tingmei WANG Qihua WANG
• 来源期刊: 摩擦（英文版）
• 年，卷（期）: 2021,（5）
• 所属期刊栏目: Research Articles
• 页码范围: 1038-1049
• 页数: 12页
• 语种: 英文

摘要

The tribological behaviors of Ti–Ni51.5 at％ alloy strengthened by finely dispersed Ni4Ti3 particles in reciprocating sliding against GCr15, Al2O3, and ZrO2 at room temperature were studied. Interestingly, the coefficient of friction (COF) suffered a sheer drop (from 0.9 to 0.2) when the aged alloy slid against GCr15 at a frequency of 20 Hz under a 20 N load without lubrication. However, severe-mild wear transition disappeared when a solutionized alloy was used. Moreover, the COF stabilized at a relatively high level when Al2O3 and ZrO2 were used as counterparts, although their wear mechanisms showed signs of oxidation. Scanning electron microscopy (SEM) and X-ray element mappings of the wear scars of the counterparts clearly indicate that the formation of well-distributed tribo-layer and material transfer between the ball and disk are pivotal to the severe-to-mild wear transition in the aged Ti–Ni51.5 at％ alloy/GCr15 friction pair. The higher microhardness and superelasticity of the aged alloy significantly accelerate the material transfer from GCr15 to the disk, forming a glazed protective tribo-layer containing Fe-rich oxides.