Acoustic Assisted Magnetic Field Induced Strain in 5M Ni-Mn-Ga Polycrystals

Magnetic shape memory alloys can be deformed in an external magnetic field by twin boundary motion. By coupling in acoustic energy the strain can be enhanced significantly, especially if the twinning stress is just above the magnetically achievable stress level. Two percent of strain can be achieved in a polycrystalline material, which showed only 0.3% strain without acoustic assistance.