Glass Forming Ability and Thermal Properties of the Mg-Based Amorphous Alloys with Dual Rare Earth Elements Addition

Abstract

The Mg₅₈Cu₃₁Y_11−xNd_x (x=0∼11) amorphous alloy rods with 3∼10 mm in diameter were prepared by Cu-mold injection method. The XRD result reveals that these entire Mg₅₈Cu₃₁Y_11−xNd_x alloy rods exhibit a broaden diffraction pattern of amorphous phase. A clear T_g (glass transition temperature) and supercooled region (about 70 K) were revealed for all of those Mg₅₈Cu₃₁Y_11−xNd_x amorphous alloy rods. The single stage crystallization of the Mg₅₈Cu₃₁Y₁₁ alloy was found to change into two stages crystallization when large amount of Nd element was added into this alloy. In parallel, the crystallization temperature (T_x) and supercooled region (ΔT_x) present a decreasing trend with increasing Nd content. The highest γ value of 0.414 occurs at the alloy compositions of Mg₅₈Cu₃₁Y₄Nd₇ and Mg₅₈Cu₃₁Y₆Nd₅ in this alloy system. Therefore, suitable addition of Nd element can obviously increase the glass forming ability for the Mg₅₈Cu₃₁Y_11−xNd_x alloy system.