The effect of primary crystallizing phases on mechanical properties of Cu₄₆Zr₄₇Al₇ bulk metallic glass composites

Cu₄₆Zr₄₇Al₇ bulk metallic glass (BMG) and its composites in plate with different thicknesses up to 6 mm were prepared by copper mold casting. Primary crystallizing phases with different microstructures and volume fractions could be obtained under different cooling rates, forming some composites with different mechanical properties. Under compression tests, the 2-mm-thick monolithic BMG has a yield strength of 1894 MPa and a high fracture strength of up to 2250 MPa at plastic strain up to 6%, exhibiting apparent "work-hardening" behavior. The 4-mm-thick Cu₄₆Zr₄₇Al₇ BMG composite containing martensite phase yields at 1733 MPa and finally fails at 1964 MPa with a plastic strain of 3.7%.