Influence of metal vapor on plasma arc stability

提高工艺效率是目前热连接工艺（如电弧焊）科学研究的重点。几年来，流程被优化、修改和控制。许多研究都集中在电弧及其边界条件（如附加工艺或基材）之间的相互作用上。到目前为止，还不能脱离表面温度单独观察金属蒸发的影响。即使对衬底进行预热也会对电弧产生影响。影响电弧的主要机制还不能确定。本课题研究了金属蒸气注入电弧形成和稳定电弧的机理。假设电弧的导电性取决于插入金属蒸气的合金元素，将研究不同钢和铝合金的稳定电位。配合指定的安装效果，可避免因工件表面升温造成的影响。因此，用激光束从隔离的基板产生金属蒸汽，并与电弧工艺正交插入。电弧电压的变化将在蒸气流入期间进行监测。通过额外的光谱分析，可以确定电弧中的电离元素。本课题的目的是确定和验证等离子弧焊的稳弧机理。此外，扩展的知识将用于使用新的稳定机制开发具有更高可靠性的高速工艺。

Increasing process efficiency is currently focused by scientific research of thermal joining processes like arc welding. For a couple of years processes are optimized, modified, and controlled. Many studies were focused on interaction between the arc and its boundary conditions e.g. additional processes or base materials. Up to now, effects of evaporated metal cannot be observed separately from the surface temperature. Even preheating of a substrate has an influence on the arc. The dominating mechanisms for influencing the arc cannot be identified definitely. In this research project mechanisms of arc formation and stabilization by metal vapor insertion are investigated. Stabilization potential of different steels and aluminum alloys will be investigated under the hypothesis that the conductivity of the arc depends on the alloying element of the inserted metal vapor. With the designated setup effects due to surface warming of the work piece can be avoided. Therefore, metal vapor is generated with a laser beam from an isolated substrate and inserted orthogonal to the arc process. Changes of the arc voltage will be monitored during this vapor inflow. With additional spectroscopic analysis an identification of ionized elements in the arc is possible.Aim of this project is to identify and to validate arc stabilizing mechanisms on plasma arc welding. Further, extended knowledge will be used for development of high speed processes with higher reliability using new stabilizing mechanisms.