Study of residual stress simulation of laser welding

In this study, simple heat source model was applied in heat transfer and residual stress analyses of laser welding. The mechanism of laser welding is too complicated for temperature distribution to be obtained. Various heat input models have been proposed to describe the laser weld profiles, thermal absorption characteristics, and temperature distributions. In the first place, we have selected one of the models, the combination of a point and a line heat sources. Despite the model's simplicity, it is able to describe a laser weld profile. Single pass laser weld joint was made with high power CO2 laser welding in order to obtain weld profiles and residual stress distributions. These data were applied to examine the results of the analyses. In the heat transfer analysis, almost the same weld profile was able to be obtained. Additionally, welding residual stress analysis was carried out based on these data. As a result, residual stress distributions near the weld metal were almost the same as measured ones. (author)