The effects of annealing and cobalt content on relaxation and the crystallization process of Zr64Ni10Al7Cu19 bulk metallic glasses were investigated. β-relaxation occurs during annealing, leading to increased endotherm before crystallization. α-relaxation during high temperature annealing (higher than Tg) affects the crystallization process. The introduction of cobalt leads to an inhomogeneous amorphous structure and two-step crystallization due to the positive mixing enthalpy between cobalt and copper. Non-affine thermal strain arising from low temperature annealing of heterogeneous structure leads to a reduced endotherm
phenomenon during relaxation on the DSC curves and a reduction in hardness
