TWI

As part of a study investigating friction stir welding (FSW) as a method for joining the lids on copper canisters for the long term storage of nuclear waste, finite element modelling was used to analyse heat flow and material flow and the development of the weld microstructure during welding so as to aid the avoidance of pores and cracks. The model incorporated heat transfer, material flow and continuum mechanics. Distortion of the copper canister as a result of thermal expansion was considered. Effects of welding speed on temperature distribution were determined, and the results of changing tool plunging position, tool geometry and the form of the joint where the lid meets the canister were assessed. Steady state solutions were compared with temperature measurements made during experiments and with results obtained from Rosenthal's analytical model.

5th International Symposium, 14-16 Sep 2004, Session 10B: Modelling, Paper 01