A Constitutive Description for Shape Memory Alloys with the Growth of Martensite Band

Materials

Weiguo Li¹  Xueliang Shen² 

[1] State Key Laboratory of Coal Mine Disaster Dynamics and Control, College of Resources and Environment Science, Chongqing University, Chongqing 400030, China;

关键词: shape memory alloy;    pseudoelasticity;    volumetric strain;    laminar microstructure;    constitutive model;   

DOI  :  10.3390/ma7010576

来源: mdpi

【 摘 要 】

Based on the experimental results and the finite element analysis, a constitutive model is proposed for two phase shape memory alloys by introducing a compensative volumetric strain into a constrained relationship between the two phases, accounting for the reduced constraint due to the growth of martensite band. The pseudoelasticity of NiTi shape memory alloy micro-tube, subjected to pure tension, is analyzed and compared with the experimental results. It can be seen that the pseudoelastic behavior, especially the phenomena of a stress drop during tension processes, can be well described with the proposed model. The proposed model separates the complicated constitutive behavior of a shape memory alloy (SMA) into simple responses arising respectively from its two phases, taking into account laminar microstructure, the thickness of martensite phase and the interaction between the two phases, and provides an easy but comprehensive method for the description of the constitutive behavior of SMAs under complex thermomechanical loading.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland