TbFe_2,as a typical magnetostrictive material,is ferrimagnetic.Its magnetostrictive property can be improved by an external magnetic field at a temperature below its Curie temperature.In this paper,the effects of high magnetic fields on the preferred orientation,phase composition and magnetostrictive property of Tb-Fe alloys during heat treatment process were investigated.It was found that the magnetostriction performance of the alloy annealed in an 11.5 T magnetic field was improved by 30%contrary to that without magnetic field.Such increase can be attributed to the increase in orientation degree of <113> caused by the high magnetic field during the heat treatment.
LIU YinWANG QiangLIU TieGAO Peng-feiSHAO Jian-guoHE Ji-cheng
In this study,the effects of high magnetic field gradients on the segregation of alloying elements,crystallized phases,and particles in alloys during solidification process and corresponding microstructures were discussed.It was confirmed that applying an external high magnetic field gradient during solidification process is an effective processing route for controlling segregation in alloys and then fabricating functional materials which have special mierostruetures and properties.Such controlling and fabrication were realized by controlling the migration of the alloying elements, crystallized phases,and particles in the liquid matrix on the basis of the Lorentz and magnetic forces.
LIU TieWANG QiangLIU YinGAO Peng-feiLOU Chang-shengHE Ji-cheng