The characteristics of the strains induced by transformation and magnetic field in ascast Ni-Mn-Ga alloy were systematically investigated.It is found that internal stress and texture introduced during casting bring th...The characteristics of the strains induced by transformation and magnetic field in ascast Ni-Mn-Ga alloy were systematically investigated.It is found that internal stress and texture introduced during casting bring the anisotropy of temperature-induced strains.However,no anisotropy of field-induced strains is induced,and the internal stress and the texture modulate only the temperature dependence of field-induced strains.Large retardance of field-induced strains was observed,which indicates the rearrangement of martensitic variants as a competition process between the stress energy and Zeeman energy.The non-continuous field dependence of strain indicates the unstable microstructure during martensitic transformation.展开更多
基金Sponsored by National Natural Science Foundation of China(50001010)National High Technology Research Plan of China(AA200132722)
文摘The characteristics of the strains induced by transformation and magnetic field in ascast Ni-Mn-Ga alloy were systematically investigated.It is found that internal stress and texture introduced during casting bring the anisotropy of temperature-induced strains.However,no anisotropy of field-induced strains is induced,and the internal stress and the texture modulate only the temperature dependence of field-induced strains.Large retardance of field-induced strains was observed,which indicates the rearrangement of martensitic variants as a competition process between the stress energy and Zeeman energy.The non-continuous field dependence of strain indicates the unstable microstructure during martensitic transformation.
