Effects of Heat Treatment on the Surface Quality and Improvement in Formability of Deformation Machined Products of Al 6061

Abstract

Continuous efforts are being made to improve the technology and the process involved in part production to meet the demands of society. Advancements in machining, as well as incremental forming, resulted in the generation of a technology that is capable of manufacturing monolithic components in a single setup. Such hybrid technological development, called deformation machining (DM), has the milling process contributing to thin structure generation and single point incremental forming (SPIF) leading to the desired geometrical deformation. Machining a material block to produce thin structure results in unwanted residual stresses in the workpiece, which hinders the part’s formability during SPIF. In the current research, stress-relieve annealing of aluminum alloy (Al 6061) is done to compensate for these residual stresses. While doing so, the optimum temperature of reheating is identified, at which the strength of the selected material is not significantly compromised. For this, preliminary microstructural investigations are carried out on the machined components at different temperatures, followed by experimental investigations. The force measurement of different samples was done during the experiments for determining the effects of heat treatment. Geometrical observations suggest that heat treatment results in better forming depth and improved forming angle, however, an increase in surface roughness is observed on the heat-treated parts.