Effects of yttrium and erbium additions on glass-forming ability and mechanical properties of bulk glassy Zr-Al-Ni-Cu alloys

Effects of yttrium and erbium additions on glass-forming ability (GFA), thermal stability and mechanical properties of glassy Zr₅₅Al ₁₀Ni₅Cu₃₀ alloy were studied. (Zr _0.55Al_0.10Ni_0.05Cu_0.30) _100-xRE_x (RE = Y, Er and x = 0, 0.5, 1.2, 3, 5 at%) metallic glasses were formed by melt-spinning and copper mold casting. It was found that the addition of Y or Er greatly enhanced the glass-forming ability, thermal stability and mechanical properties of Zr₅₅Al ₁₀Ni₅Cu₃₀ alloy. The alloys containing 1-3 at% Er can be cast into glassy rods with a diameter of 15 mm, which is larger than the critical diameter (10 mm) of the base alloy in the present work. With the addition of 1 at% Y, supercooled liquid region ΔT_x, of the base alloy was extended from 89 to 102 K, compressive strength was increased from 1650 to 1800 MPa and plastic strain reached a value as high as 3.5%.