Fabrication of new Cu34Pd2Zr48Ag 8Al8 bulk glassy alloy with a diameter of 30 mm

Abstract

Glass-forming ability (GFA) of Cu36-x,PdxZr 48Ag8Al8 alloys was examined with the aim of developing a bulk glassy alloy with large critical diameter. It was found that the addition of 2 at% Pd significantly improved the GFA of the Cu 36Zr48Ag8Al8 alloy. The fully glassy alloy rod with a diameter of 30 mm was successfully fabricated for the Cu 34Pd2Zr48Ag8Al8 alloy using a copper mold casting method. The further increase of Pd content causes the decrease in the GFA. For the Cu36-xPdxZr 48Ag8Al8 alloys, the Tg and T x increase monotonously with increasing Pd content, while T l shows a minimum value at 2 at% Pd, resulting in a maximum γ (= Tx/(Tg + Tl)) value at 2 at% Pd. The increase or γ parameter may be tne reason tor the significant improvement ot the GFA ot the quinary alloy. © 2007 The Japan Institute of Metals.