Computerized distortion minimization of laser beam welded complex components

激光焊接是一种快速、灵活的连接工艺。尽管能量沉积较低，但激光束焊接会导致部件变形，从而不符合尺寸公差。因此，需要额外的加工步骤，如热矫直或机械矫直。在众多的研究工作中，基于仿真的调查有助于更好地理解扭曲和简单几何形状的部件扭曲的增强预测。然而，对于复杂的几何形状，数值检测适当的工艺参数，以最小的组件变形导致成本上升，由于增加计算费用。此外，建立数值模型的任务包含许多非自动化的处理步骤，需要大量的用户专业知识。这些复杂的几何形状模型的大小，因此需要一个新的方法的失真计算和最小化在一个合理的时间内，因此，该建议的目的是开发和验证一个新的计算机化的和有效的方法预测适当的工艺参数的激光束焊接复杂的几何形状与最小的组件变形。该提案的另一个目标是演示一种可能的方法来自动化单个建模步骤，并简化用户对过程的控制。为了根据数值方法预测适当的工艺参数，必须将复杂的几何形状划分为子区域-类似于所谓的局部-全局方法，但具有不同的连接操作。随后，关于残余应力和部件变形，这些分区必须进行数值分析。然后可以应用子区域的计算的失真来计算整个复杂几何形状的失真。该方法的应用与优化算法的使用相结合，将有助于预测适当的工艺参数，以使焊接几何形状中的部件变形最小。

Laser beam welding is a fast and flexible joining process. Despite the low energy deposition, laser beam welding leads to component distortions and, thus, to non-compliance with dimensional tolerances. Therefore, additional processing steps like thermal or mechanical straightening are required. Simulation based investigations within numerous research works have contributed to a better understanding of distortions and to an enhanced prediction of component distortions of simple geometries. For complex geometries, however, the numerical detection of appropriate process parameters for minimal component distortion leads to rising costs due to increasing computational expenses. Moreover, the task to build the numerical model contains many non-automated processing steps and requires a lot of user expertise. The size of these complex geometry models therefore requires a new approach for the distortion computation and minimization within a reasonable time.Hence, the aim of the proposal is the development and validation of a new computerized and efficient method for the prediction of appropriate process parameters for laser beam welded complex geometries with minimal component distortion. An additional goal of this proposal is the demonstration of a possible way to automate the single modelling steps and to simplify user control of the procedureIn order to predict the appropriate process parameters based on numerical methods, a complex geometry has to be divided into subareas -- similar to the so called local-global-method, but with different joining operations. Subsequently, with regard to the residual stresses and the component distortion, these subareas have to be numerically analyzed. The computed distortions of the subareas can then be applied to compute the distortion of the whole complex geometry. The application of this method in combination with the use of optimization algorithms will facilitate the prediction of appropriate process parameters for minimal component distortion in welded geometries.