Burnishing Effects on Friction Stir Welding of Al-Alloy 7075 T6
Burnishing process is widely used to produce excellent surface finish, hardness and compressive residual stresses by plastically deforming the workpiece surface for the various types of materials such as steel, copper, brones, aluminum and thier alloys. Many works have studied the effect of burnishing on surface characteristics of different materials. In this work the optimum parameters of burnishing process on Friction Stir Welded joints of Aluminum 7075 T6 alloy are investigated by testing the effect of different burnishing parameters i.e. table speed, burnishing force, and transverse feed rate on Friction Stir Welded joints and study the mechanical behavior before and after burnishing process. It has been found that good surface finish is achieved at low burnishing speed and transverse stroke with burnishing force around 200 N, high micro-hardness and high bending strength can be obtained at low burnishing speeds and low transverse stroke, with high burnishing force where as a high tensile strength is obtained at high burnishing speeds due to directional deformation of grains and the orientation of residual stresses.
