Orientation dependence of thermal and mechanical hysteresis in Ni51Fe18Ga27Co4 single crystals

The orientation dependence of thermal ΔТ and mechanical Δσ hysteresis was investigated in Ni51Fe18Ga27Co4 single crystals as-grown with isobaric (shape memory effect) and isothermal (superelasticity) experiments. Single crystals oriented along the [001]-direction show a high reversible deformation of 001 ЭПФ ε = (4,0 ± 0,2) % for martensitic transformations, small thermal hysteresis ΔТ = (22 ± 2) K and mechanical Δσ001 = (47 ± 2) МПа hysteresis, as compared with to single crystals oriented along the [110]-direction. Such orientation dependence is determined by the contribution of the L10-martensite under the εdetw in deformation of transformation