Surface Enhancement by Friction Stir Burnishing

Abstract

By applying the burnishing process, not only surface roughness but also residual stress state and micro hardness within the surface layer can be improved as usual. . In this study, a new type burnishing tool that rubs on the machined surface with high rotational speed is proposed, and the capability of the enhancement of the material/mechanical properties on the surface by the proposed tool is reported. The tip of the burnishing tool stirs within the thin surface layer under high strain rate in this process. After the friction stir burnishing on 0.45% carbon–steel with the carbide tip tool, very hard layer over 800HV was generated. The thickness of the hardened layer is 20µm to 40µm.