Anomalous Temperature Dependence of Crystalline-to-Amorphous Transformation Induced by High-Pressure Torsion in Zr50(Cu,Al)50

Martensite phases of Zr50Cu50 and Zr50Cu44Al6 were deformed by high-pressure torsion (HPT) at different temperatures ranging from 253 to 473K. Microstructural observations revealed that the crystalline-to-amorphous transformation induced by HPT showed remarkable temperature dependence: an increase in deformation temperature up to 473K significantly increased the fraction of the amorphous structure. This result suggests that the lattice instability near martensitic transformation temperature promotes crystalline-to-amorphous transformation, which is coherent to the generalized Lindemann criterion of defect-induced amorphization. [doi:10.2320/matertrans.M2013049]