Ni-Ti形状记忆合金热压缩变形行为的研究

Research on Hot Compressive Deformation Behavior of Ni-Ti Shape Memory Alloy

采用热模拟压缩实验在变形温度650～1050℃、应变速率0.01～1 s^(-1)、变形量20%～60%条件下对Ni-Ti形状记忆合金的热压缩变形行为及变形组织进行分析。随着压缩温度、应变速率或变形程度的增大,压缩试样的动态再结晶增加明显。当应变速率一定,压缩实验的温度越高,Ni-Ti形状记忆合金的流变应力越低。1050℃在应变速率0.1 s^(-1)压缩时Ni-Ti形状记忆合金的峰值应力仅为650℃压缩时的19.4%。

The hot compressive deformation behavior and deformation microstructure of Ni-Ti shape memory alloys were analyzed by thermal simulation compression experiment under the temperature of 650-1050℃,strain rate of 0.01-1 s^-1and deformation of 20%-60%.The dynamic recrystallization of the compressed samples increase obviously with the increase of compression temperature,strain rate and deformation degree.When the strain rate is constant,the higher the temperature compression experiments,the lower the stress of Ni-Ti alloy.The peak stress of Ni-Ti shape memory alloys compressed at1050℃and strain rate of 0.1 s^-1is only 19.4%of the alloy compressed at 650℃.