Thermal Stability and Mechanical Properties of Mg–Y–Cu–M (M = Ag, Pd) Bulk Amorphous Alloys

Abstract

Magnesium-based bulk amorphous alloys with a diameter of 7 mm for Mg 65 Y 10 Cu 15 Ag 5 Pd 5 were produced by a metallic mold casting method. The glass transition temperature (T g ), crystallization temperature (T x ), the temperature interval of the supercooled liquid region (ΔT x = T x - Tg) and the melting temperature (T m ) are measured to be 437, 472, 35 and 707 K, respectively, for the Mg 65 Y 10 Cu 15 Ag 5 Pd 5 alloy. The simultaneous addition of Ag and Pd to Mg-Y-Cu system causes a steep decrease in T m and an increase in the reduced glass transition temperature (T g /T m ), leading to an increase in the glass-forming ability. The Mg-Y-Cu-(Ag, Pd) bulk amorphous alloys have a high compressive fracture strength of 770 MPa. The simultaneous addition of Ag and Pd is useful for the improvements of glass-forming ability and fracture strength.