Control of plastic deformation in Cu50Ta50 metallic glass by insertion of Cu crystalline cores

Abstract

Abstract The tensile characteristics and deformation mechanisms of Cu-Ta metallic glasses with the insertion of Cu crystalline cores are investigated using molecular dynamics (MD) simulations. The effects of different Cu crystalline core diameters (D Cu ), experiment temperatures (T), and Cu crystalline core numbers (N) are studied. The results show that the plasticity of the Cu-Ta MGs is significantly improved by inserting Cu crystalline cores. The Shockley dislocations (<112>) make up the majority, and the FCC structures mainly transform into the HCP structures in the Cu crystalline cores. As increasing D Cu , the shear transformation zones (STZs) form more severely, the fraction of atoms with the high shear strain increases, and the tensile strength reduces. As increasing T, the STZs formation is fainter and most intense at 100 K, the fraction of atoms with the shear strain greater than 0.5 (f0.5) and the tensile strength reduce, while the fraction of atoms with the shear strain greater than 0.3 (f0.3) increases. As changing N, the STZs formations in the samples with the N = 2 and 8 are more pronounced, the f0.5 of the samples with the N = 1 and 8 are lower than those in the other cases, and the tensile strength reduces as the N increases.