EFFECT OF FRICTION ON BARRELLING AND COLD WORKABILITY LIMITS OF AL-4%COPPER ALLOY DURING COLD UPSET FORGING AND FEA MODELING

Abstract

Experiments were carried out to study the deformation behavior of Al-4%Cu binary alloy. Cast billets with 4%Cu by weight were upset at room temperature. Lubrication and aspect ratio (H₀/D₀) were studied as process parameters. Results show reduced barreling with lubrication. Micro hardness tests revealed a non uniform deformation with in the specimen. Micro structural features support the non uniformity in deformation from both axial and transverse direction. A 4 mm square grid, marked at the equatorial surface of sample, and deformation was studied by using an integrated PC based video recording system. Finite element analysis of deformation behavior of cold upsetting process was carried out in both dry and lubricated conditions with aspect ratios of 1.0 and 1.5. Rigid-flexible contact analysis was performed for the forming process. The comparison of various stress values obtained after 50% deformation from finite element analysis and measurement of grids using vision system were in close range.