Multiple bifurcations and local energy minimizers in thermoelastic martensitic transformations  

作　　者：Chen Xuan Shurong Ding Yongzhong Huo 

机构地区：[1]Department of Mechanics and Engineering Science,Fudan University

出　　处：《Acta Mechanica Sinica》2015年第5期660-671,共12页力学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grants 11461161008 and 11272092)

摘　　要：Thermoelastic martensitic transformations in shape memory alloys can be modeled on the basis of nonlinear elastic theory.Microstructures of fine phase mixtures are local energy minimizers of the total energy.Using a one-dimensional effective model,we have shown that such microstructures are inhomogeneous solutions of the nonlinear Euler-Lagrange equation and can appear upon loading or unloading to certain critical conditions,the bifurcation conditions.A hybrid numerical method is utilized to calculate the inhomogeneous solutions with a large number of interfaces.The characteristics of the solutions are clarified by three parameters：the number of interfaces,the interface thickness,and the oscillating amplitude.Approximated analytical expressions are obtained for the interface and inhomogeneity energies through the numerical solutions.Thermoelastic martensitic transformations in shape memory alloys can be modeled on the basis of nonlinear elastic theory.Microstructures of fine phase mixtures are local energy minimizers of the total energy.Using a one-dimensional effective model,we have shown that such microstructures are inhomogeneous solutions of the nonlinear Euler-Lagrange equation and can appear upon loading or unloading to certain critical conditions,the bifurcation conditions.A hybrid numerical method is utilized to calculate the inhomogeneous solutions with a large number of interfaces.The characteristics of the solutions are clarified by three parameters：the number of interfaces,the interface thickness,and the oscillating amplitude.Approximated analytical expressions are obtained for the interface and inhomogeneity energies through the numerical solutions.

关 键 词：Thermoelastic martensitic transformation MICROSTRUCTURES Nonlinear elasticity BIFURCATION Energy minimizer 

分 类 号：O343.6[理学—固体力学]