Improved mechanical behavior of Cu-Ti-based bulk metallic glass by in situ formation of nanoscale precipitates

摘要

The mechanical properties of Cu_(47)Ti_(34)Zr_(11)Ni_8, Cu_(47)Ti_(33)Zr_(11)Ni_8Fe_1, and Cu_(47)Ti_(33)Zr_(11)Ni_8Si_1 bulk metallic glasses prepared by copper mold casting are investigated. Room temperature compression tests reveal fracture strengths above 2000 MPa, Young's moduli around 100 GPa and elastic strains slightly exceeding 2.0%. Only Cu_(47)Ti_(33)Zr_(11)Ni_8Si_1 exhibits distinct plastic strain due to a unique composite microstructure with in situ formed nanoscale precipitates in the glassy matrix.