The effect of Cu on the plasticity of Fe–Si–B–P-based bulk metallic glass

A (Fe0.76Si0.096B0.084P0.06)99.9Cu0.1 bulk metallic glass exhibits strength of 3.3 GPa and a large plastic deformation of about 3.1% in compression. A well-developed vein pattern on the fracture surface and easily distinguishable highly dense multiple shear bands on the side surface of the rod specimen near the fracture surface were observed. The unusual deformation behavior could be due to the existence of a large number of α-Fe nanocrystals (less than 10 nm) embedded in a glassy matrix.