NUMERICAL SIMULATION OF MICROSTRUCTURE GROWTH CAUSED BY TWINING AND DETWINNING IN SHAPE MEMORY ALLOYS
In this paper we propose a thermoelastic dynamic approach for modeling the microstructure growth and decay in shape memory alloy patches. Microstructures are associated with an energy minimizer of a variational problem,in which the potential energy function is constructed as a non-convex function of the chosen order parameter. Square to rectangle transformations and rectangle variant re-orientations are modeled by simulating the transformations of system states from one local minimum of the potential energy function to another. A Ginzburg term is introduced as a function of strain gradients to take into account the energy contributions from the domain walls. We employ the conservation law for linear momentum to obtain the governing equations for the thermoelastic dynamics. The proposed model allows a robust implementation of all typical boundary conditions, but is strongly nonlinear. Numerical results are presented with various simulated microstructures by using finite element analysis. Laminated structures and needle-like microstructures, which are often observed in experimental investigations, are obtained. Simulated microstructure growth and decay caused by boundary stress loadings are also presented.
thermoelastic shape memory alloys nonlinear dynamics mesomechanics microstructures
Linxiang Wang
Department of Ocean Science and Enineering, Zhejiang University, Hangzhou 310028 China Institute of Mechatronic Engineering,Hanghou Dainzi University,Hangzhou 310037 China
国际会议
广州
英文
204-209
2010-12-17（万方平台首次上网日期，不代表论文的发表时间）