Transient behaviour of torque and process efficiency during inertia friction welding

Abstract

Process efficiency is a crucial parameter for inertia friction welding (IFW). A new method is developed to determine the efficiency by comparing the workpiece torque used to heat and deform the joint to the total torque. Particularly, the former is measured by torque load cell attached to the non-rotating workpiece, while the latter is determined from the deceleration rate of flywheel. The efficiency measured for IFW of AISI 1018 steel is inputted into analytical heat balance calculation of the upset length and finite element thermo-mechanical modelling of the extruded flash profile. The calculated results are consistent with the respective experiment data. The transient behaviour of torque and efficiency is discussed based on the energy loss and the bond formation.