Investigating of the influence of non-stationary processes in arc plasma on the depth penetration in high frequency TIG welding

研究电弧等离子体非平稳过程对高频 TIG 焊熔深的影响

• 批准号: 390246097
• 负责人: Professor Dr.-Ing. Uwe Reisgen
• 金额: --
• 依托单位: Institut für Schweißtechnik und Fügetechnik (ISF)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/390246097?language=en
• 关键词: Investigating; influence; non; stationary; processes

The advantage of high frequency TIG (HF-TIG) welding in comparison to conventional TIG welding is a significant concentration of energy density in arc either a higher welding depth or welding velocity. The underlying physical interactions of a conventional TIG arc welding with high frequency pulse current are not investigated sufficiently: in fact, the effect of frequency on the depth welding effect was mentioned [EWM-2002] but the effect of pulse current on the depth of penetration was not investigated.Increase of the weldings depth by HF-TIG-welding is not caused by increasing the power of energy source of welding, but it is derived from the combination of physical mechanisms (Arc contraction, behaviour of the current density in arc, fluid dynamics in weld pool etc.) These mechanisms are associated with the direct interaction of HF-pulse currents with the plasma and the metal (as well as its evaporation) and with the changes of characteristics of Anode processes. This should be considered for development of self-consistent model.The aim of this project is the development of a self-consistent model, which describes the physical phenomena in HF-TIG-welding and provides the characterization of mechanisms to increase the depth of welding using these processes. This leads to a considerable knowledge of the effect of increasing welding depth by HF-TIG-welding which is basically well-known, the expression of the dependency of the effects on the concerning complex physical mechanisms are not described sufficiently. The project provides the essential insight of the interactions between a TIG-arc welding and a superimposed high frequency pulse current.The self-consistent model will be developed on the basis of coupled component models which consider the present knowledge about essential physical parameters and interactions mechanisms between the arc, the pulse high frequency current and the metallic base material respectively weld pool. Based on this model, the mechanisms for increasing the welding depth by HF-TIG-welding dependent on the technical parameters will be determined. Furthermore, evaluating and quantifying the influencing variables of this mechanism in interaction with the welding parameters such as pulse shape, frequency and current will be considered. For this purpose, theoretical and experimental methods will be used.The gained knowledge particularly discloses the potential of technology possibilities of HF-TIG welding in the whole and the usage of the high frequency-pulse to increase the welding depth. With that technology, the advantage of a high work piece will be useful with simultaneously more efficient heat input and better energy usage as an alternative for the conventional TIG welding.

与常规TIG焊接相比，高频TIG（HF-TIG）焊接的优点是电弧中的能量密度显著集中，焊接深度或焊接速度更高。常规TIG电弧焊与高频脉冲电流的潜在物理相互作用尚未得到充分研究：实际上，[EWM-2002]中提到了频率对深度焊接效果的影响，但没有研究脉冲电流对熔深的影响。HF-TIG焊的焊接深度增加不是由于增加焊接电源的功率，但它是由物理机制（电弧收缩、电弧中电流密度的行为、熔池中的流体动力学等）的组合导出的。这些机制与高频脉冲电流与等离子体和金属（以及其蒸发）的直接相互作用以及阳极过程特性的变化有关。本项目的目的是开发一个自洽模型，它描述了HF-TIG焊接中的物理现象，并提供了使用这些过程来增加焊接深度的机制的表征。这导致了HF-TIG焊接增加焊接深度的效果的相当多的知识，这基本上是众所周知的，效果对相关复杂物理机制的依赖性的表达没有得到充分描述。本研究以耦合分量模型为基础，考虑了电弧、高频脉冲电流和熔池之间的物理参数和相互作用机理，建立了自洽模型，并对高频脉冲电流和熔池之间的相互作用机理进行了研究。在此基础上，确定了HF-TIG焊工艺参数对焊接深度影响的机理。此外，评估和量化的影响变量，这种机制的相互作用与焊接参数，如脉冲形状，频率和电流将被考虑。为此，将使用理论和实验方法。所获得的知识特别揭示了HF-TIG焊接技术的整体可能性和使用高频脉冲来增加焊接深度的潜力。利用该技术，高工件的优点将是有用的，同时更有效的热输入和更好的能量使用作为传统TIG焊接的替代方案。