为了探讨温度和应变率对NiTi记忆合金相变转换率的影响,本文利用准静态试验机和分离式Hopkinson压杆的恒应变率技术对板条状和圆柱状试样进行了不同应变率的试验,同时通过改变温度检查相变转换的速度,结果表明:在较低的10-2/s应变率下,NiTi记忆合金伪弹性变形过程自身就会有6.5℃温升,这意味着在高应变率下其性能是温度与率的耦合效应;随外界环境温度的增加,NiTi记忆合金的相变恢复速率由递增趋于一稳态值,当温度超过365K时,恢复速率趋缓至约0.014mm/s;随应变率增加,相变转换率会趋于极限,即应力诱发的奥氏体向马氏体相转化阶段在应变率超过6000/s时基本不变,表明更高的应变率已不能引起NiTi相变转换.
参考文献
[1] | K.Otsuka;X.B.Ren .Recent developments in the research of shape memory alloys[J].Intermetallics,1999(5):511-528. |
[2] | Yu D;Zhang BM;Liang J .A changeable aerofoil actuated by shape memory alloy springs[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2008(1/2):243-250. |
[3] | 于月民,丁元柱,于丽艳.SMA动作器结构变形的主动控制[J].黑龙江科技学院学报,2008(02):118-121. |
[4] | André Musolff,毛谦德,刘耀乙.带有形状记忆致动器的自适应机翼[J].工程设计学报,2003(01):26-31. |
[5] | Sia Nemat-Nasser;Jeom Yong Choi;Wei-Guo Quo .High Strain-Rate, Small Strain Response of a NiTi Shape-Memory Alloy[J].Journal of engineering materials and technology,2005(1):83-89. |
[6] | Sia Nemat-Nasser;Wei-Guo Guo .Superelastic and cyclic response of NiTi SMA at various strain rates and temperatures[J].Mechanics of materials,2006(5/6):463-474. |
[7] | Sia Nemat-Nasser;Jeom-Yong Choi;Wei-Guo Guo;Jon B. Isaacs .Very high strain-rate response of a NiTi shape-memory alloy[J].Mechanics of materials,2005(2/3):287-298. |
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