摘要
采用透射电镜、X射线衍射仪和示差热分析仪系统分析了Ni49Ti36Hf15合金的相变行为及其形状记忆效应。结果表明,Ni49Ti36Hf15合金的热马氏体变体间构成典型的自协作组态,主要呈矛头状、镶嵌块状和楔状3种形态,亚结构主要为(001)复合孪晶。随着热循环次数的增加,相变温度降低,经50次热循环后,相变温度随热循环次数增加变化趋势不明显。固溶处理Ni49Ti36Hf15合金在20～184℃范围内弯曲变形时,呈现良好的形状记忆效应,其最大可恢复应变可达3%。形状恢复率随着弯曲变形温度的增加而下降,当弯曲变形温度大于317℃时,形状恢复率下降为0。
The microstructure, phase transformation and shape memory properties of Ni49Ti36Hf15 alloy have been systematically investigated by means of TEM, X-ray diffraction spectrum and DSC. It is shown that the martensite variants of NiTiHf alloy mainly show spear-like, mosaic-like and wedge-like morphologies. The substructure of martensite variant was confirmed to be (001) compound twin. The transformation temperatures were decreased with increasing of thermal cycling until 50 cycles, then the temperatures tend to stable. When the solution treated Ni49Ti36Hf15 alloy was tested by bending method between 20-184°C, the alloy exhibit good shape memory effect, with maximum complete recoverable strain up to 3%. With decreasing of bending deformation temperature, the shape recovery ratio decreases, however when bending deformation temperature was over 317°C, the shape recovery ratio decreases to 0.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2003年第1期48-50,共3页
Journal of Functional Materials
关键词
NiTiHf高温形状记忆合金
相变
形状记忆效应
Bending (deformation)
Hafnium alloys
Martensite
Morphology
Nickel alloys
Titanium alloys
X ray diffraction analysis
