The Role and Practical Significance of Geysler Alloys in Modern Materials Science

Heusler alloys represent an important class of functional intermetallic materials with highly tunable structural, electronic, magnetic, mechanical, and thermoelectric properties. Their scientific significance is associated with the possibility of controlling physical characteristics through chemical composition, atomic ordering, valence-electron concentration, and structural phase transformations. Full-Heusler, half-Heusler, inverse-Heusler, and quaternary Heusler systems have attracted considerable attention because of their potential applications in spintronics, thermoelectric energy conversion, magnetic refrigeration, shape-memory technologies, sensors, actuators, and emerging quantum materials. This article examines the structural characteristics, functional properties, practical applications, and research perspectives of Heusler alloys. Particular attention is paid to their half-metallicity, spin polarization, martensitic transformations, magnetocaloric behavior, and thermoelectric performance. The role of computational materials science, density functional theory, and machine-learning-assisted materials design in developing new Heusler compounds is also discussed.