Structural and diffusional phase transformations in liquid-quenched Mg₈₅Y₉Zn₆ ribbons below the bifurcation temperature

Abstract

In-situ and simultaneous small- and wide-angle scattering measurements of liquid-quenched Mg₈₅Y₉Zn₆ alloy ribbons were performed to examine phase transition during isothermal annealing at the temperatures below the bifurcation temperature, where long-period stacking ordered (LPSO) structures are not formed yet in the previous work. Even below the temperature, sluggish structural transformation destroying hcp stacking sequence was observed, and development of in-plane and inter plane cluster structures, as imperfect LPSO structure, became noticeable at long time annealing. The characteristic time for structural transformation showed well-defined thermally activated process with Q = 173.6 +/- 14.4 kJ/mol.