The characterization of plastic flow in three different bulk metallic glass systems

Plastic deformation behaviors of Zr_52.5Al₁₀Ni₁₀Cu₁₅Be_12.5, Mg₆₅Cu₂₅Gd₁₀ and Pd₄₃Ni₁₀Cu₂₇P₂₀ bulk metallic glasses (BMGs) are studied by using the depth-sensing nanoindentation, macroindentation and uniaxial compression. The significant difference in plastic deformation behavior cannot be correlated to the Poisson's ratio or the ratio of shear modulus to bulk modulus of the three BMGs, but can be explained by the free volume model. It is shown that the nucleation of local shear band is easy and multiple shear bands can be activated in the Zr_52.5Al₁₀Ni₁₀Cu₁₅Be_12.5 alloy, which exhibits a distinct plastic strain during uniaxial compression and less serrated flow during nanoindentation.