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

The effect of partial substitution of Ti for Zr on the glass-forming ability was studied in Cu₅₀Zr_45-xTi_xAl ₅ (x = 0, 2.5, 5, 10) alloys by using thermal analysis and X-ray diffractometry. The glass transition temperature, T_g, of Cu ₅₀Zr_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 Cu₅₀Zr₄₅Al ₅ alloy promotes the glass formation. The maximum diameter for glass formation by injection casting increased from 3 mm for Cu₅₀Zr ₄₅Al₅ alloy to 4 mm for Cu₅₀Zr _42.5Ti_2.5Al₅ alloy.