HEAT-TRANSPORT IN MELT FLOWING PAST THE KEYHOLE IN DEEP PENETRATION WELDING

A theoretical analysis is carried out on the transfer of heat into the workpiece in deep penetration welding. Special attention is given to the effect of melt flow on the transfer efficiency. It is found that the widely used model by Noller, which disregards the melt flow past the keyhole, overestimates the heat transfer. The difference is most significant at high welding speeds. The temperature distribution obtained in this work is more confined, leading to a shorter weld pool.