Self-consistent modelling of arc, material transfer and seam structure in gas metal arc welding

该项目的目的是开发、验证和应用一个过程模型，用于对气体保护金属弧焊产生的连接区进行数值描述，包括电弧中所有相关的物理过程以及焊丝电极和母材上的熔体。计算应在物理上自洽，并依赖于工艺参数。它应该支持关于所产生的渗透剖面、接缝结构和对母材的热输入的有根有据的陈述。开发的流程模型符合行业要求，即作为行业4.0的一部分的所有加入流程的完全可模型性。为了保证过程模型的高信息量，同时考虑相关子过程的不同时间尺度，熔滴脱离模型与熔池模型顺序耦合。子模型的组合是通过用熔滴脱离模型计算的源项来实现熔池模型中的电弧和材料转移的特性来实现的。在该项目的第一部分，将扩大现有的熔滴脱离和熔池模型，以实现物理上自洽和省时的气体保护焊模拟。在随后的模型应用过程中，将确定所开发的建模方法是否可以转移到其他具有实际意义的焊接任务和材料上。所开发的工艺模型能够详细分析气体保护焊中的因果链以及在广泛的参数范围内产生的焊缝的数值可预测性，从而能够物理地确定气体保护焊工艺本身以及所使用的设备的发展。

The aim of the project is to develop, validate and apply a process model for the numerical description of the resulting joining zone of gas metal arc welding including all relevant physical processes in the arc as well as the melts at the wire electrode and parent material. The calculation should be physically self-consistent and dependant on the process parameters. It should enable well-founded statements regarding the resulting penetration profile, seam structure and heat input into the parent material. The developed process model meets the requirements of the industry for complete modelability of all joining processes as part of industry 4.0. In order to guarantee a high informative value of the process model while simultaneously taking into account the different time scales of the relevant sub-processes, a model of droplet detachment is sequentially coupled with a weld pool model. The combination of the sub models is achieved by implementing the characteristics of the arc and the material transfer in the weld pool model by source terms, which are calculated using the droplet detachment model. In the first part of the project, existing models of droplet detachment and weld pool will be enlarged to enable physically self-consistent and time-efficient modelling of gas metal arc welding. In the course of the subsequent model application, it will be determined whether the developed modelling approach can be transferred to other welding tasks and materials of practical relevance. The developed process model enables a detailed analysis of the cause and effect chain in gas metal arc welding as well as the numerical predictability of the resulting weld in a wide range of parameters, thus enabling a physically determined development of the gas metal arc welding process itself as well as the equipment used.