Thermodynamic and mechanical properties of Cu–Zr–Al–Ti bulk metallic glasses

The thermodynamic and mechanical properties of Cu46Zr46-xAl8Tix (x = 0, 1, 2, and 3 at.%) bulk metallic glasses (BMGs) were investigated. The experimental results indicate that the Cu46Zr46Al8 and Cu46Zr45Al8Ti1 alloys achieve good glass formation ability (GFA), whereas that of both Cu46Zr44Al8Ti2 and Cu46Zr43Al8Ti3 alloys are weak. The thermogravimetric curve is nonlinear from the glass transition temperature to the completion of crystallization temperature and may be related to the reaction of disordered atoms and oxygen and nitrogen atoms. The Cu46Zr45Al8Ti1 BMG with the work-hardening ability in these alloys has a large yield strength of 1870 MPa and a fracture strength of 2060 MPa. The average incubation time of the serrated flow in the elastic–plastic stage with the high work-hardening index is 1.3706 s, which is higher than that of the plastic deformation stage (0.9398 s) with the low work-hardening index. The nonlinear thermogravimetric curve of the supercooled liquid region and the average incubation time of the serrated flow are crucial to further understand the oxidizability and nitriding capacity of the disordered atoms and the mechanism of plastic strain in the metallic glass field