Fabrication of ternary Mg–Cu–Gd bulk metallic glass with high glass-forming ability under air atmosphere

A new Mg₆₅Cu₂₅Gd₁₀ alloy having significantly improved glass-forming ability (GFA) has been developed. In this article, we show that the ternary Mg₆₅Cu₂₅Gd₁₀ bulk metallic glass with diameter of at least 8 mm can successfully be fabricated by a conventional Cu-mold casting method in air atmosphere. The critical cooling rate for glass formation was estimated on the order of magnitude of approximately 1 K/s. When compared with the GFA of Mg₆₅Cu₂₅Y₁₀ alloy, the significantly improved GFA of Mg₆₅Cu₂₅Gd₁₀ alloy cannot be explained by ΔT_x and T_rg values.