THERMAL AND MAGNETIC-PROPERTIES OF STRESS-INDUCED MARTENSITES IN NI-MN-GA ALLOYS

The stress-induced transformation of single crystals of Ni-Mn-Ga ferro magnetic Heusler ordered alloys to new martensitic structures has been investigated. The intermartensitic transformations, whenever they occ ur, were registered during heating by calorimetry, dilatometry and mag netic susceptibility measurement, showing up a step-like strain recove ry, small endothermal effects, and an abrupt change of the low-field m agnetic susceptibility. During intermartensitic transformations, betwe en modulated and unmodulated lattices, as well as during the final tra nsformation to the parent austenitic phase, noticeable anomalous chang es in the specific magnetization were observed.