摘要: 本文研究了振动时效对约束态下NiTi形状记忆合金的力学性能与相变行为的影响，用自制的拉伸机测试了振动与未振动NiTi合金在自由加热过程中的回复应变，用万能拉伸实验机测试了NiTi合金的力学性能，用DSC测试了NiTi合金的相变行为。结果表明，随着振动幅度的增加，NiTi合金丝在自由加热过程中输出的两段回复应变减小；随着振动时间的延长，NiTi合金输出的回复力减小，最多约80MPa。DSC结果表明约束态振动后再变行马氏体逆相变温度升高，相变潜热减小，而继承变形马氏体和热诱发马氏体相变潜热增加。所有结果均直接或间接表明，振动时效降低了NiTi形状记忆合金产生的回复力。这可能是由于振动在NiTi合金中产生了微观塑性变形，降低了回复力。

Abstract: The mechanical properties and transformation behavior of NiTi shape memory alloy under constant strain constraint with and without vibration were investigated by using tensile test machine, CSM002 type material test equipment and differential scanning calorimeter (DSC). With increasing the amplitude of vibration, the two-stage recovery strain of NiTi alloy obtained during free heating decreased. With increasing the time of vibration, the recovery stress of NiTi alloy generated under constraint also decreased. The DSC results showed that the second reverse transformation peak temperature of NiTi alloy after vibration under constraint increased slightly during the subsequent heating. The transformation heat of the two reverse transformation peaks had an opposite change, the first one increased, while the second one decreased. All these results indicated that the recovery stress of NiTi alloy generated under constant constraint decreased due to vibration. These could be caused by microscopic plastic deformation during vibration.