Ball Burnishing Parameters Affecting the Residual Stress of the Zr65Cu15Al10Ni10 Metallic Glass

Ball burnishing (BB) is a superfinish operation performed to improve surface, subsurface quality and mechanical proprieties. In the present study, a bi-dimensional (2D) finite element model (FEM) was developed to confirm that the BB of Zr65Cu15Al10Ni10 bulk metallic glass (BMG) affects its microstructures, roughness, and residual stress. As a part of the process, the influence of different parameters on the residual stress surface in the axial and transverse directions was investigated. The topography of the burnished samples is analyzed by an atomic force microscope (AFM) and scanning electron microscope (SEM). The ball burnishing process was performed, and the improvements in the surface and subsurface integrity were found to be significant. Residual stress after BB was found to be affected by burnishing force to a statistically significant extent. The Zr-based BMG displayed significant improvements in surface roughness and residual stress following the burnishing process. The topographical and morphological results of the treated samples show a variation of irregularity of the burnished faces and the formation of the shear bands (SBs) below the hardened layer. The FE simulation results indicate that the residual stress values and depth are increased by the increase of burnishing force. The ball burnishing process enhanced the surface topography and produce the residual stress on the Zr-BMG samples.