Force estimation in flow forming of Al6101 T6 stepped cylinder-experimental analysis and mathematical modelling

Abstract

Flow forming is a cold-forming process that is widely used for fabricating axisymmetric products. The present paper tries to propose a mathematical formulation for the flow forming of a stepped cylinder. An analytical model based on the upper bound method has been proposed. The mathematical formulation was then validated with the experimental trial on Al6101 T6 material. Forward flow forming operation was employed with a single roller assembly. The present investigation showed that the flow-forming forces depend significantly on axial forces while the circumferential forces were found to be less significant. The circumferential force was found to be much lesser than the axial force. The measured radial force was found to be within 20% of the measured axial force. The experimental trial showed the force variation in the process increased with thickness reduction per pass but the trend was not uniform. The increase in force in successive passes was found to be less than the previous pass for similar thickness reduction. The differences between the predicted force and experimental force were within 11%.