摘要
本文系统研究了Cu-Zn-Al形状记忆合金中形变度对形状回复的影响。从马氏体变态再取向的微观模型出发,阐明了预变形度ε对形状回复率η的影响规律及其本质。存在一个临界变形度ε_L(～2％),当ε<ε_L时,η随ε呈线性地增加(η=K_1ε-K_2d^(-1/2)),当ε>ε_L时,η随ε的增大而下降。同时讨论了拉伸变形与弯曲变形间的对应关系,得出弯曲变形时欲获最佳回复率的临界曲率半径R_L≈12mm。从热力学出发导出形状开始回复温度与变形度的关系T_s=A_s+(-1/2E_1ε~2+E_2ε)/ΔS_Tβ_1→M。所导出的定量规律,均与实验结果相吻合。
A systematic investigation of the influence of deformation on shaperecovery has been put forward in Cu-Zn-Al shape memory alloys in this paper.Starting at the model of the re-orientation of martensitic variants, the principle andessentiality of the influence of the amount of pre-deformation ε on shape recoveryrate η is elucidated.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1989年第4期A235-A243,共9页
Acta Metallurgica Sinica
