NiTi形状记忆合金沙蚀磨损的机敏行为

来源期刊：中国有色金属学报2000年第z1期

论文作者：徐久军 严立 朱新河 严志军 杨胜 杨大智

文章页码：188 - 191

关键词：形状记忆合金； 砂蚀磨损； 机敏摩擦学特性

Key words：shape memory alloys； sand erosion wear； smart tribological characteristic

摘    要：研究了Ti-50.94%Ni(摩尔分数 )形状记忆合金的耐磨性 ,试验温度为 70℃ ,砂水比为 0.2 ,累计磨损时间 30h。结果表明 ,NiTi合金表现出良好的耐磨性 ,扫描电镜仅观察到轻微的磨损。采用四棱锥金刚石压头模拟砂粒与试样的接触过程 ,并用原子力显微镜对压痕进行定量研究 ,观察发现 ,NiTi合金压痕呈星形 ,反映出明显的弹性变形特征 ,说明材料应力应变非线性关系和伪弹性变形行为对砂蚀磨损耐磨性具有重要贡献 ,进一步证明形状记忆合金的机敏摩擦学特性。

Abstract: The tribological properties of Ti-50.94%Ni (mole fraction) shape memory alloy (SMA) were studied at 70 ℃. The mass ratio of sand to water was 0.2 and the total wear time was 30 h. The results show that NiTi alloys have an excellent wear resistance. The worn topography is very smooth by SEM observation. The contact behavior of sand particle engaging to the testing sample surface was simulated by pyramid like diamond tip. The indention was measured by AFM. The star like indention on the NiTi alloys surface shows that the nonlinear relationship between the stress and strain and the pseudo elasticity have great contribution to the sand erosion wear resistance. The concept of smart tribological characteristic of SMA is defined.