Effect of Titanium on Glass-forming Ability of Cu-Zr-Al Alloys

Abstract

The effect of partial substitution of Ti for Zr on the glass-forming ability was studied in Cu₅₀Zr_45−xTi_xAl₅ (x=0, 2.5, 5, 10) alloys by using thermal analysis and X-ray diffractometry. The glass transition temperature, T_g, of Cu₅₀Zr_45−xTi_xAl₅ alloys decreased from 707 K at x=0 to 700 K at x=2.5, and keeps almost constant with further increase of x. On the other hand, the crystallization temperature, T_x, decreased gradually from 767 K at x=0 to 741 K at x=10. The partial substitution of Zr by Ti in Cu₅₀Zr₄₅Al₅ alloy promotes the glass formation. The maximum diameter for glass formation by injection casting increased from 3 mm for Cu₅₀Zr₄₅Al₅ alloy to 4 mm for Cu₅₀Zr_42.5Ti_2.5Al₅ alloy.