Effect of yttrium and neodymium additions on aging characteristics and high temperature tensile properties of Mg-10 mass%Gd and Mg-10 mass%Dy alloys

Mg-10 mass% Gd and Mg-10 mass% Dy alloys have high strength at high temperatures and exhibit good ductility. In this study, 1 or 2 mass% yttrium or neodymium was added to these binary alloys in order to increase high temperature strength and reduce the material cost, and the effect of the third alloying elements on their aging characteristics and high temperature tensile properties were investigated. Additions of Y or Nd to Mg-10 mass% Gd or Dy alloys promote remarkable precipitation hardening by aging at high temperatures. Neodymium addition is found to be very effective to increase strength. It is clear that the Mg-10 mass% Gd-2 mass% Nd alloy exhibits the highest strength among investigated alloys and its strength is superior to that of the conventional heat resistant magnesium and aluminum alloys at temperatures > 200 deg C.