Synergistic effect of crystalline metal on the plasticity of bulk metallic glasses under uniaxial synchro-compression

摘要

A uniaxial synchro-compression test of a cylindrical bulk metallic glass (BMG) specimen along with a crystalline metallic ring having an inner diameter much larger than the specimen's diameter and thereby without radial confinement on the BMG specimen was performed. The plastic deformation behavior of a conventional Zr_(65)Cu_(17.5)Ni_(10)Al_(7.5) BMG under synchro-compression with a cupper ring was investigated. It was found that remarkably plastic deformation in the inherently brittle BMG could occur under the uniaxial stress state as the loading area of the cupper ring was sufficiently large, and multiplication of the shear band on the synergistically deformed BMG specimen could be accomplished. The synergistic effect of the crystalline metal on the plastic deformation behavior of the BMG was attributed to the reduced thermal softening extent inside the shear bands that resulted from the restraining effect of the copper ring on the spring-back action of the testing machine.