Ductility improvement of Zr-Cu-Ni-Al glassy alloy

We studied the relationship between the phase diagrams and formation of crystalline inclusions in cast samples in order to improve the ductility of Zr-Cu-Ni-Al bulk amorphous alloy. A Zr₅₀Cu₄₀Al₁₀ bulk amorphous alloy with a composition close to the ternary eutectic point has no crystalline inclusions and possesses superior mechanical properties of tensile strength σ_B=2000 MPa, Young’s modulus E=107 GPa and Vickers hardness HV=580. Oxygen embrittlement of Zr-Cu-Ni-Al bulk amorphous alloys can be avoided in the Zr₅₀Cu₃₀Ni₁₀Al₁₀ bulk amorphous alloy, which exhibits superior ductility and resistance to oxidation. Furthermore, we tried to improve ductility by cold rolling by making use of the apparent work-softening phenomenon of Zr-Cu-Ni-Al bulk amorphous alloys. Preliminary studies indicated that cold rolling to produce a fine slip-band structure, which enabled uniform deformation and superior deformability, is an important procedure for improving the ductility of Zr-Cu-Ni-Al bulk amorphous alloys.