Unusual room temperature ductility of a Zr-based bulk metallic glass containing nanoparticles

Highly ductile Zr65Al7.5Cu27.5 bulk metallic glass (BMG) containing nanometer scaled fcc phase was obtained by copper mold casting. Room temperature compression tests revealed superior mechanical properties of the alloy: yielding stress of 1670 MPa, Young's modulus of 90 GPa, elastic strain of 2%, and especially a remarkable plasticity of over 50%. The marginal BMG is a useful model system to examine the nanocrystal coalescence model and the shear-transformation-zone model proposed for large scale plastic deformations of metallic glasses. (c) 2007 American Institute of Physics.