时效处理对TiNiCr形状记忆合金相变的影响

Effect of Aging Treatment on Transformation Behavior of TiNiCr Shape Memory Alloys

摘要:

利用差示扫描量热仪(DSC) 、扫描电镜(SEM)和D/max2500PC全自动X射线衍射仪研究了不同时效处理制度下TiNiCr合金相变温度的变化规律。结果表明，该合金随着时效温度增加，逆马氏体相变点As、Af上升，但当时效温度高于700 ℃时，相变点As、Af降低。该合金在冷却过程中经历了B2→R→B19′两阶段一级相变。通过SEM和XRD衍射研究表明，该合金经时效处理产生了Ti3Ni4析出相诱发了R相变。

Abstract:

Transformation behavior of TiNiCr shape memory alloys with different aging treatment was investigated by DSC, scanning electron microscopy (SEM) and the D/max2500PC automatic X-ray diffraction equipment (XRD). The results indicate that with increasing of the aging temperature, the transformation temperature As and Af increase but they decrease after 700 oC and TiNiCr alloy exhibits B2→R→B19′ two-stage martensitic transformation during cooling. Lots of Ti3Ni4 precipitants from aging treatment induce R phase transformation.