Stabilization of the vapor capillary by additional intensity maxima along the beam axis

深熔激光束焊接提供了生产具有高长宽比（大深度和小宽度）的焊缝的可能性，并且相对较少的热量输入到组件中。激光辐射可通过蒸汽毛细管（锁孔）深入材料内部。通过改变输入蒸汽毛细管的能量，可以显著影响动态过程的行为。本研究项目的目的是在恒定的工艺和系统参数下，通过有针对性的光学设计，增加深熔激光焊接的焊接深度，同时减少气孔和飞溅的形成。在激光深熔焊接中，在给定的工艺参数下，锁孔深度通常受到毛细管底部强度降低的限制。该项目是基于这样一个假设，即增加可实现的毛细深度以及毛细动力学的稳定可以通过以适当的轴向光束整形的形式修改能量输入来实现。

Deep penetration laser beam welding offers the possibility of producing welds with a high aspect ratio (great depth with small width) with comparatively low heat input into the component. The laser radiation can penetrate deep into the material through the vapor capillary (keyhole). By varying the energy input into the vapor capillary, the dynamic process behavior can be significantly influenced. The aim of this research project is to increase the welding depth in deep penetration laser welding while at the same time reducing the formation of pores and spatter through targeted optical design with otherwise constant process and system parameters. The challenge lies in the fact that the keyhole depth for given process parameters in laser deep penetration welding is usually limited by the reduced intensity at the capillary bottom. The project is based on the assumption that an increase of the achievable capillary depth as well as a stabilization of the capillary dynamics can be achieved by a modification of the energy input in the form of a suitable axial beam shaping.