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Information × Registration Number 0205U000967, 0102U000316 , R & D reports Title Martensite transformations and associated functional properties in materials with non-trivial structural and magnetic states popup.stage_title Head Koval Yu. N., Registration Date 18-02-2005 Organization Institute for metal physics NAS Ukkraine popup.description2 The microstructure, orientation relationship and mobility of the interphase boundaries created during the reversible martensite transformation in solids have been studied experimentally along with theoretical analysis. The equations obtained allow predicting higher relative mobility of the interphase boundary for martensite crystal with internal twins in comparison to martensite microstructure with dislocations. The definition of the interphase coherency is introduced and discussed its role in the interphase boundary mobility. For the first time, the effect of high formability up to (60-70)% has been detected on the multicomponent Ti-Ni-Hf-based melt-spun ribbons in the temperature range of supercooled liquid between the glass transition temperature Tg and crystallization temperature Tx; its value depends on the heating and strain rates. The increase of plasticity of the Ni-Al-based superalloys up to 2% has been reached thanks to simultaneous alloying by Re and B, and by introduction of the phase transformation plasticity /martensite transformation/, thus, increase the ability to practical applications at high temperatures. For quasibinary ZrCu-based alloys, good correlation is established between the martensite transformation temperatures observed experimentally and calculated in the framework of model based on actual parameters of crystalline lattice and features of the electronic band structure. A set of prospective materials for shape memory effect induced by magnetic field is proposed with magnetic domain structure reordered during transformation by the martensite crystal lattice. The conditions for realization of the shape memory effect induced by magnetic field are defined as follows: high specific magnetic moment per atom, large magnetic anisotropy energy, small specific heat of transformation, tetragonal and orthorhombic distortions of the crystalline lattice induced by magnetic field and high mobility of the interphase boundaries. Product Description popup.authors popup.nrat_date 2020-04-02 Close