Effect of Severe Plastic Deformation and Ultrarapid Quenching on the Properties of Magnetic Shape Memory Alloys near the Ni_2MnGa Composition

摘要

The effect of ultrarapid quenching from melt and subsequent severe plastic deformation by torsion in Bridgman anvils on the temperatures of martensitic (T_M) and magnetic (T_C) phase transitions in magnetic shape memory alloys has been investigated. The features of the crystal structure and magnetic, electric, and optical properties of Ni_2MnGa-based alloys with different degrees of structural ordering are discussed. The effect of doping with copper and cobalt on the properties of nonstoichiometric Ni_(50)Mn_(28.5)Ga_(21.5) alloy is con_sidered.