Deformation Behavior of a Zr_(55)Al_(10)Ni_5Cu_(30) Bulk Metallic Glass at High Temperatures

摘要

The deformation behaviors of a Zr_(55)Al_(10)Ni_5Cu_(30) bulk metallic glass under tensile loading at different initial strain rates and temperatures in the supercooled liquid region were investigated. The Zr_(55)Al_(10)Ni_5Cu_(30) bulk metallic glass has showed either homogeneous superplastic or inhomogeneous deformation depending on the test condition. The deformation behavior of Zr_(55)Al_(10)Ni_5Cu_(30) alloy in the supercooled liquid region could be classified into three types. The flow stress in the supercooled liquid region generally became lower with increasing temperatures and decreasing strain rates. As the temperature increased, the strain rate which led to the peak elongation increased. The crystallization of glass phase of the alloy occurred during testing at low strain rates and higher temperature in the supercooled liquid region, and eventually, resulted in strain hardening and brittle fracture.