A non-isothermal phase field-finite element study of magnetic-induced deformation for ferromagnetic shape memory alloy

A non-isothermal phase field model is established to study the magnetic-thermo-mechanical coupled deformation of ferromagnetic shape memory alloy (FSMA). The model and boundary conditions for NiMnGa FSMA single crystal are numerically realized by finite element method. The phase field-finite element simulation investigates the loading level dependent and loading frequency dependent magnetic-thermo-mechanical coupled deformation of FSMA, especially the evolution of martensite domain structure, magnetic domain structure and temperature field. The simulation results show that the maximum magnetic-induced strain decreases with the increase in loading level due to the increasing impediment of temperature rise on martensite reorientation. The block of high temperature rise to the subsequent martensite reorientation depends on the proportion of domain where the local highest temperature rise formed rather than the value of local highest temperature rise. Therefore, the maximum magnetic-induced strain and local highest temperature rise are non-monotonic versus the loading frequency. In different loading frequencies, the larger the domain occupied by local highest temperature rise, the more the residual martensite variant preferred by stress field, and the smaller the maximum magnetic-induced strain.

Automated summary

A non-isothermal phase field model is used to study the magnetic-thermo-mechanical coupled deformation of ferromagnetic shape memory alloy. The simulation results show that the maximum magnetic-induced strain and local highest temperature rise decrease with increasing loading level, and their relationship with loading frequency is non-monotonic.