Effect of isothermal annealing temperature on microstructure and mechanical properties of Cu45Zr45Ag7Al3 amorphous alloy

Abstract

Abstract Bulk amorphous alloys, as a material with broad application prospects, are highly expected in many cutting-edge applications. However, its plastic deformation relies on highly localized shear bands, resulting in brittle fracture characteristics of materials with low plastic strain as a whole. Therefore, strengthening and toughening of amorphous alloys is one of the key topics in the research of amorphous applications. In this paper, the effects of different isothermal annealing temperature on the microstructure and uniaxial compression properties of Cu45Zr45Ag7Al3 amorphous alloy were studied by means of differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that Cu10Zr7, AlCu2Zr, Cu8Zr3 and Al2Zr phases precipitated successively from the amorphous alloy matrix with the increase of annealing temperature, and the fracture strength and plastic strain increased first and then decreased; At an isothermal annealing temperature of 741 K, the precipitated nanocrystalline Cu10Zr7 phase can improve the fracture strength of the alloy; when the annealing temperature rises to 746 K, the strength of the alloy decreases slightly, but the plasticity increases; with the continuous increase of annealing temperature, the plasticity of the alloy decreases and the strength continues to increase; As the annealing temperature continues to increase, the fracture strength of the alloy decreases, exhibiting significant brittle fracture characteristics.