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铜材料激光深熔焊接的应用受到蒸气毛细管处和熔池内发生的不稳定性的限制。到目前为止，复杂的对策，如激光功率的振荡或空间光束振荡，被应用于防止所导致的缺陷的形成。该项目FASTLAS研究了高进给速率和激光功率下的激光焊接，作为提高铜激光焊接焊缝质量和工艺效率的策略。IFSW的诊断和实验资源将与PIMM在激光材料加工建模和仿真领域的能力相结合，IFSW将应用在线X射线摄像技术来量化毛细管的几何形状和熔池中的流体动力学。将确定吸收的激光功率和局部温度的分布。由于铜激光焊接过程中的高度动态相互作用，这将以2 kHz的时间分辨率和约20 µm的空间分辨率来完成。基于这些测量，PIMM将开发一个焊接过程的综合模型。特别是，几何形状依赖的激光功率和气相的耦合将被包括在模型中，因为这些对于理解导致焊接缺陷的产生的物理过程以及在高进给速率下焊接时过程的稳定性是至关重要的。基于这一全面的多物理模型，将开发一种用于预测和优化焊接工艺的工具。通过在高进给速度和激光功率下焊接来稳定毛细管，从而提高焊缝质量的策略是基于项目合作伙伴的初步调查。随着进给速度的增加，毛细管几何形状的稳定性被实验和理论上发现，这导致了焊缝质量的增加。然而，在熔池和气相中的耦合，热力学和流体动力学的相互作用还不知道。这尤其适用于以超过10米/分钟的进给速度使用超过10千瓦的激光功率加工铜。鉴于激光技术的稳步发展，预计在不久的将来，将以合理的成本提供多个现有的激光功率。随后，焊缝深度仅为几毫米的铜激光焊接将在工业环境中得到应用。该项目将有助于促进电力电子产品的生产技术，尤其是在电动汽车领域。如果成功，将鼓励开发高性能激光器和相关系统技术。合作的目的是促进知识交流和共同利用各自的资源。有长期合作的目标。

The application of deep penetration laser welding of copper materials is limited by instabilities occurring at the vapour capillary and within the melt pool. Up to now, complex countermeasures, such as oscillation of the laser power or spatial beam oscillation, are applied to prevent the resulting formation of defects. The project FASTLAS investigates laser welding at high feed rates and laser powers as a strategy to increase the seam quality and the process efficiency in laser welding of copper. In a cooperative approach, the diagnostics and the experimental resources of the IFSW will be combined with the competencies of the PIMM in the field of modelling and simulation of laser material processing.The IFSW will apply the online X-ray videography to quantify the geometry of the capillary and the fluid dynamics in the melt pool. The distribution of the absorbed laser power and the local temperatures will be determined. This will be done with temporal resolutions of 2 kHz and spatial resolutions of about 20 µm due to the highly dynamic interactions in the copper laser welding process. Based on these measurements, the PIMM will develop a comprehensive model of the welding process. In particular, the geometry dependent incoupling of the laser power and the gas phase will be included in the model, since these are crucial for the understanding of the physical processes that lead to the creation of welding defects and to the stabilization of the process when welding at high feed rates. Based on this comprehensive, multiphysical model, a tool for the prediction and optimization of the welding process will be developed.The strategy of stabilizing the capillary by welding at high feed rates and laser power and thereby increasing the quality of the resulting weld seams is based on preliminary investigations by the project partners. With increasing feed rate, a stabilization of the capillary geometry was found experimentally and theoretically, which resulted in an increase of the seam quality. However, the interaction of incoupling, thermodynamics and fluiddynamics in the melt pool and gas phase are not yet known. This applies in particular to the processing of copper with laser powers of more than 10 kW at feed rates of more than 10 m/min. Given the steady progress in laser technology, it is expected that in the near future a multiple of the today established laser powers will be available at reasonable costs. Laser welding of copper with seam depths of a few millimetres at very high feed rates will then be applicable in industrial environment.The project will contribute to the promotion of production technology for power electronics, most prominently in the field of e-mobility. If successful, incentives will be created to develop high-performance lasers and associated systems technology. The cooperation is intended to facilitate the exchange of knowledge and the joint use of the respective resources. A long-term cooperation is targeted.