Characterization of preferential orientation of martensitic variants in Ni52Mn24Ga24 single crystal
单晶Ni52Mn24Ga24中马氏体变体择优取向的物理表征

The preferential orientation of martensitic variants in the single crystal Ni 52Mn 24Ga 24 has been characterized by various methods, such as optical microscopy observation, strain measurement, and magnetic field-induced strain (MFIS). The origin of the spontaneous preferential orientation of variants was attributed to the internal stress with a magnitude of about 2.45 MPa, as calculated based on the experimental data. We found that the preferential orientation of variants produced the anisotropy, different effective elastic constants and distribution of magnetic domain, between two equivalent crystallographic directions of 001] and 010]. The resulting MFIS properties, such as saturated MFIS, saturated field, hysteresis effect and initial magnetic field have been discussed in detail.