NiTi合金中马氏体相的低频力学谱研究  

THE MARTENSITIC PHASE IN NiTi ALLOY STUDIED BY LOW FREQUENCY MECHANICAL SPECTROSCOPY

作　　者：沈中城[1] 严勇健[1] 杨洪[1] 

机构地区：[1]苏州市职业大学(苏州学院筹)现代测试技术与仪器研究所,苏州215104

出　　处：《物理学进展》2006年第3期442-444,共3页Progress In Physics

摘　　要：我们用最近研制成功的LMA型低频力学谱测试系统对NiTi合金马氏体相进行了在很大频率范围内（0．003～1Hz）的低频等温力学谱和温度谱的测量．我们研究的形状记忆合金NiTi（Ni50．2at％）试样长34mm，直径1mm细丝．经一定热处理，分别在333K．343K和353K做了内耗随频率的变化的测量。实验表明：频率越小，内耗越大，也就是内耗随频率减少而增大。同时我们采用阶梯升温的方法在八个温度下每个温度测量三种频率（1Hz，0．1Hz，0．01Hz）的内耗，结果清楚地表明：不同频率下，内耗峰都出现在372K（99℃）。而且频率越低，峰高越高。这是具有相变峰的特点：相变峰的峰温不随测量频率不同而变化，相变峰高度随频率减少而增大。我们还测量了在1Hz与0．5Hz频率下内耗随温度的变化。本文用马氏体相的位错理论初步讨论了上述实验结果。We have performed low frequency isothermal mechanical spectroscopy and temperature spectroscopy measurements in a very large frequency range by a new LMA type low frequency mechanical spectroscopy measurement system. Shape memory alloy NiTi （Ni50.2 ate）sample with length 34 min and diameter 1 min has been measured as a function of frequency at 333 K,343 Kand 353 K. From these results it has been shouwn that the later is the frequency, the higher is the mechanical spectroscopy valne. Simaltaneusly we have measured mechanical spectroscopy in NiTi using step heating manner at various temperatures and frequencies, the peaks over all appeared 372 K. This paper proposed the model related with damping capacity of martensitic phase in the shape memory alloy. We here address the mechanical spectroscopy peaks by the dislocation theory of martensitic interracial structure and mobility.

关 键 词：马氏体 低频内耗 NITI 位错模型 

分 类 号：O469[理学—凝聚态物理] O485[理学—电子物理学]