Enhanced ductility in a Zr65Cu15Al10Ni10 bulk metallic glass by nanocrystallization during compression

A highly deformable Zr65Cu15Al10Ni10 bulk metallic glass is reported in this letter. The 1 mm and 2 mm rods can be compressed into flakes at room temperature without macroscopic global brittle failure even though a crack initiated after the strain was over 25%. Examinations using high-resolution transmission electron microscopy revealed that nanocrystallites appeared in the amorphous matrix during compression, retarding the sudden propagation of the dominant shear bands and promoting the branching of multiple shear bands. As a consequence, the ductility was significantly improved.