Numerical simulation of dynamic behavior in controlled short-circuit transfer process

Abstract

There is a high demand for increased efficiency and quality in welding, especially for gas metal arc welding, which has wide industrial applications. Moreover, the independent control of the heat input and the deposition rate is also important for some applications such as dissimilar material welding and the wire arc additive manufacturing process which needs low heat input despite a higher deposition rate. A controlled short-circuit transfer process is expected to be a high-quality and high-productivity process. In this process, short-circuit transfer is stably and periodically repeated to enable the low heat input and high deposition rate, and the independent control of the heat input and the deposition rate was achieved to a certain extent. However, control factors for the heat input and the deposition rate in this process are not clear enough because of the lack of investigations for the process. In this study, we have explored the welding phenomena of a controlled short-circuit transfer process by developing an arc-electrode unified model. In this model, short-circuit transfer process was conducted, including the extinction and the reignition of the arc plasma, and the dynamic behavior of the arc and the molten metal was observed. The results observed were in good agreement with the experimental measurements. Furthermore, we also determined the control factors for the heat input to electrodes.