Large reversible magnetostrain of a Ni₃₀Cu₈Co₁₂Mn₃₇Ga₁₃ single crystal

The reversible magnetostrain was investigated in a Ni₃₀Cu₈Co₁₂Mn₃₇Ga₁₃ single crystal undergoing the magnetic-field-induced reverse martensitic transformation. A 0.14% reversible magnetostrain was monitored in the as-grown single crystal and it decreased to 0.08% after magnetic field cycling. By 5 cycles of thermo-mechanical training under 38 MPa, the reversible magnetostrain could be effectively increased to 0.47%, which is the largest value as reported in the samples without the constraint of external stress. It was revealed that the preferential orientation of the martensitic variants was formed after thermo-mechanical training, thus contributing to the large reversible magnetostrain.