冷热循环对CuZnAl形状记忆合金性能的影响

Effects of Thermal Cycles on the Properties of CuZnAl Shape Memory Alloys

采用不同的热循环温度、不同的预应变量ε、不同的复合稀土加入量以及透射电镜方法,研究了冷热循环对CuZnAl形状记忆合金的相变温度、记忆性能的影响.研究结果表明,冷热循环使合金的相变温度提高5～6℃.增大合金的预应变量ε,会减少达到稳定双程形状记忆性能的循环训练次数,同时合金的形状回复率有所提高,但预变形量大于3.6％以后,合金的形状回复率下降.合金中加入复合稀土量小于0.10％时,对合金的记忆性能影响不大,但未加复合稀土的合金,冷热循环大于1800次以后,其形状记忆性能开始下降.

The effects of thermal cycles on the properties of CuZnAl shape memory alloys under different heating temperatures, pre-deformations ε and amounts of complex rare earth mixture added were researched with electronic microscopes. The results indicate that thermal cycles can increase the transformation temperature Ms of the alloys by 5-6℃. Increasing the pre-deforma-tion ε will decrease the necessary cycle times for stable two-way-shape memory property. However the shape recovery rate of the alloys will decrease when the pre-deformation exceeds 3.6%. The shape memory property of the alloys will change insignificantly if the amount of rare earth added is less than 0.10%. But the alloys without rare earth will have worse shape memory property after thermal cycles reach 1800 times.