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 Zr55Al10Ni5Cu30 alloy were studied. (Zr0.55Al0.10Ni0.05Cu0.30)100-xREx (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 Zr55Al10Ni5Cu30 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 (delta) Tx 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%.