(北京有色金属研究总院，有研亿金新材料股份有限公司，北京 102200)
摘 要: 为研究冷轧对TiNi形状记忆合金性能的影响，采用差示扫描量热仪(DSC)和X线衍射(XRD)对不同冷轧变形量下TiNi形状记忆合金的非晶化行为进行研究，并利用硬度测试方法研究TiNi形状记忆合金非晶晶化对硬度的影响。结果表明：在第一次加热曲线上，在低温(293~373 K)范围内没有相应的马氏体相变吸热峰，却在(623~693 K)温度范围内有1个明显的放热峰，该放热峰对应着非晶区域的晶化过程，这与XRD结果相一致。研究发现变形量超过30%以后出现非晶化现象，冷轧非晶的体积随变形量的增加而增大，其中冷轧60%的TiNi合金的非晶体积分数可达30%左右。且在623 K左右发生非晶晶化，这与硬度测试结果相一致。
关键字: 形状记忆合金；冷轧；差示扫描量热仪；非晶化；
（GRIKIN Advanced Materials Co., Ltd., General Research Institutes for Nonferrous Metals, Beijing 102200, China）
Abstract:In order to investigate the effect of cold rolling on properties of TiNi shape memory alloy, the amorphization behavior of TiNi shape memory alloys under different deformation was studied by differential scanning calorimeter (DSC) and X-ray diffraction(XRD). The effect of recrystallization with different heat treatment was studied by hardness test. Results show that the reverse martensitic transformation peak is not observed during the first heating at the rate of 20 K/min in the as-rolled samples, but one exothermic peak is observed at 623-693 K, which is associated with the amorphous crystallization process. And that mechanical amorphisation by cold rolling occurs above 30% deformation and the volumetric fraction of amorphous increasing with deformation increasing, in which with the volumetric fraction of 30% amorphous in the 60% rolled deformation sample. And that the amorphous regions recrystallise at 623 K, which agree with hardness test.
Key words: shape memory alloy; cold rolling; differential scanning calorimeter (DSC); amorphisation
