The Effect of Dy Substitution on the Glass-Forming Ability and Crystallization Behavior of Mg65Cu10Ni10Y10Zn5 Metallic Glass

摘要

The glass-forming ability, thermal stability, and crystallization behavior of Mg65Cu10Ni10Y10-xZn5Dyx (x = 0, 2, and 4) alloys were investigated. The partial substitution of Dy for Y increases the activation energy of the first crystallization, but it decreases the glass-forming ability and thermal stability. Analyses on crystallization kinetics suggest that the substitution of Dy for Y decreases the nucleation rate. In addition, the examination of the crystallization phase after the isothermal annealing indicated that Dy addition suppresses the formations of Mg2Cu and Mg and that it promotes the formation of MgZn crystalline phase. The decreasing glass-forming ability with the Dy substitution can be attributed to the narrower supercooled liquid region, higher Gibbs free energy, and the change of crystallization products.