The influence of the heat source model selection on mapping of heat affected zones during surfacing by welding

The paper compares forms and dimensions of heat affected zones determined on the basis of analytical descriptions of temperature fields caused by different models of heat source. In the first case, a single-distributed volumetric heat source model reflecting only the impact of an electric arc was assumed. In further considerations, bimodal heat source models were applied. The first one consists of a volumetric heat source model of weld reinforcement (of melted electrode material) and a surface model of an electric arc. In the second one a bimodal source is the sum of volumetric heat source models of weld reinforcement and an electric arc. Calculations are based on the example of submerged arc welding of a rectangular S355 steel element. The results of numerical simulations were verified experimentally, confirming the argument that it is necessary to include the bimodal heat source in temperature field modelling, which takes into account the temperature rises caused by the heat of melted electrode material.