Mechanical properties of monolithic Zr_(62)Al_8Ni_(13)Cu_(17) bulk metallic glass

摘要

We present mechanical properties of monolithic bulk metallic glass (BMG) Zr_(62)Al_8Ni_(13)Cu_(17) under uniaxial compression and tensile tests. It is found that the Zr_(62)Al_8Ni_(13)Cu_(17) BMG exhibits pronounced plasticity of nearly 14% without catastrophic failure upon compression. However, it is destroyed under tension in a brittle manner. High energy X-ray diffraction has been used to detect the structural change in this BMG during both conditions. No deformation-induced nanocrystallization is detected in a 55% strained sample under compression while it only appears in the fracture-affected region upon tension. No excess free volume is obviously found in the fractured samples. We suggest that monolithic BMG alloys with small differences in atomic affinity and atomic sizes among components might have high plasticity under compression.