Laser beam welding is a precise and efficient technique for joining metal materials using laser radiation. Critical for the adaption into productivity-driven applications is the feed rate at which laser beam welding is performed. However, high-speed laser beam welding is accompanied by humping formation – the periodic accumulation of beadlike protuberances along the weld seam. For commonly available laser intensity distributions (e.g. Gaussian, top hat) it has been shown that humping is related to the transition of the keyhole geometry from a narrow shape to an elongated shape. However, the impact of complex beam profiles, such as ring-shaped intensity distributions, on the geometry of the laser-material interaction zone in high-speed laser welding is not yet fully understood. The goal of this work is to examine the relationship between different ring-core intensity distributions and the formation of the laser-material interaction zone in high-speed laser welding. In-situ synchrotron X-ray imaging is used to capture the process behaviour during single track experiments conducted for this study. Key parameters such as keyhole depth, width, and area are derived and correlated with the applied core-ring intensity distributions in the subsequent image analysis step. Additionally, surface properties of the weld tracks using profilometer measurements are analysed and humping characteristics such as height and spatial frequency are assessed.
Keywords
- Beam Shaping
- High-Speed Laser Welding
- X-Ray Imaging