Change in microstructure during training of a Ni50Mn29Ga21 bicrystal

The change in microstructure during training of a Ni50Mn29Ga21 bicrystal was investigated by electron backscatter diffraction in a scanning electron microscope. The martensitic variants form macro and micro twins which are twin related with each other. The twin plane is of type. To achieve magnetic field induced strain in Ni–Mn–Ga alloys, a training process was applied. This process consists of successively compressing the sample along two axes. As a result the twinning stress is reduced and the twinning strain is maximized.