We made a unique investigation comparing twinning stress in Ni-Mn-Ga magnetic shape memory single crystals from various producers. We found that provided the crystal is free of significant defects, then it always shows the same universal temeperature dependence of twinning stress. The finding is relevant both for physical understanding of the magnetic shape memory effect as well as for the use of the material in smart applications. More details in the publication:
Musiienko, D., Nilsén, F., Armstrong, A., Rameš, M., Veřtát, P., Colman, R. H., … & Straka, L. (2021).
Effect of crystal quality on twinning stress in Ni–Mn–Ga magnetic shape memory alloys.
Journal of Materials Research and Technology, 14, 1934-1944.
https://doi.org/10.1016/j.jmrt.2021.07.081
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