Energy and force analysis of linear friction welds in medium carbon steel

The linear friction welding process is rapidly developing into an important manufacturing technology for high quality joining of engineering materials. The energy required for linear friction welding is an important issue due to economic and environmental reasons, but is not currently fully understood. This paper describes a comprehensive evaluation of the energy input during linear friction welding of a medium carbon steel with different process parameters. This calculation is based on an analysis of force and displacement data from the machine, which takes momentum into account. The analysis shows that energy input to the weld is minimised with high frequencies and rubbing velocities; however, there is a considerable amount of energy lost in oscillating the machine tooling under these conditions. Furthermore, analysis of the force indicates that a peak load occurs just before the samples being aligned, which is probably caused by ploughing of the samples during welding.