NiTi(0.46wt%Cu)形状记忆合金中的诱发R相变

The Stress Induced R Phase Transformation in a NiTi(Cu)Shape Memory Alloy

本文用电阻和 x-射线衍射的方法,对含0.46(wt)%Cu 的 NiTi 形状记忆合金中的 R相变进行了研究。结果表明,在本试验条件下,该合金中未能观察到 R 相变。然而,通过热循环或应力热循环可诱发出 R 相变,导致(011)B_2峰明显地分裂为(011)_R 和(0ì1)_R 两个次峰。应力循环的作用要大于热循环。特别是当低于 M_s 点时,马氏体大量生成的同时,(011)_R 峰比(0ì1)_R 峰更快消失。

A preliminary study was carried out on the R phase transformation in a NiTi (0.46%Cu)alloy by means of electric resistance and X-ray diffraction.It was shown that under normal condition,the R phase transformation was not found,but occured under thermo or stress cycles, resulting in a obviously splitting of the (001)_(B2) Bragg peak to two subpeaking of (011)_R and (0ì1)_R.The effect of stress cycles on the R phase transformation is greater than that of thermo cycles.Espe- cially (011)_R peak disappears faster than (0ì1)_R below Ms while large quantities of martensite occured.