Defect structures and phase transitions of FeRh alloys deformed at high speed deformation

Fe–Rh alloys of Rh concentrations ranging from 40 to 50at.% and of B2 phase were deformed by use of a compression machine capable of running tests at high speeds of impact. Induced complicated substructures and phases were examined by X-ray diffraction (XRD), transmission electron microscopy (TEM), and positron annihilation spectroscopy (PAS). A characteristic arrangement of L10 domains was observed, along with very small transformed A1 domains and dispersed in the residual B2 matrix. On the basis of the experimental results, we suggest a coupling of a pair of shears along {112}〈11−1〉B2 for the transformation mechanisms from B2 to L10 and A1 phases.