The use of diffraction techniques for understanding structure–property relationships in Heusler alloys

Heusler compounds are intermetallic alloys that are capable of a wide range of unique properties such as magnetocaloric, thermoelectric, and magnetic-shape-memory effects, antiferromagnetism, superconductivity, and they can even act as topological insulators. These multifunctional behaviors make Heusler alloys prime candidates for numerous smart device applications. However, their specific properties critically depend on their crystalline structures, chemical order, structural phase transformations, and crystallographic texture. Thus, as compositions and processing parameters are varied it becomes essential to be able to accurately characterize the structure of these materials at various scales. This paper provides a brief review of diffraction-based characterization techniques ideally suited for the characterization of Heusler alloys with examples from our previous works including use of synchrotron, neutron, and electron diffraction, especially as a function of temperature and/or magnetic field to explain important phenomena demonstrated by Heusler alloys.