Thermal efficiency decision of variable polarity aluminum arc welding through molten pool analysis

• Published in: International journal of heat and mass transfer Vol. 138; pp. 729 - 737
• Main Authors: Jeong, Hunchul, Park, Kyungbae, Baek, Sungjin, Cho, Jungho
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-08-2019; Elsevier BV
• Subjects: Aluminum; Aluminum alloys; Aluminum base alloys; Aluminum oxide; Arc; Arc heating; Computer simulation; DCEN; DCEP; Decision analysis; Efficiency; Flow-3d; Gas tungsten arc welding; GTAW; Melt pools; Numerical analysis; Polarity; Reverse polarity; Straight polarity; Thermal efficiency; Thermodynamic efficiency; Variable polarity; Volume of fluid; Flow-3d; GTAW; Arc; Aluminum; DCEP; DCEN; Straight polarity; Reverse polarity; Thermal efficiency; Variable polarity; Volume of fluid
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2019.04.089

•Thermal efficiency of reverse polarity arc welding of aluminum never has been reported till now.•New thermal efficiency decision method based on numerical analysis is suggested.•The method is comparison of weld bead of three dimensional simulation to experiment.•The analysis model is already verified through the authors’ previous over ten reports.•The revealed thermal efficiency is 95% which is 3.8 times larger than that of straight polarity.
One of several solutions to enhance the weldability of aluminum alloy is removing the aluminum oxide layer on the surface by adopting variable polarity arc welding. The authors’ previous experimental research on the variable polarity arc welding of aluminum alloy showed that reverse arc polarity has larger heat input efficiency than a straight polarity. Furthermore, the authors have already developed a numerical analysis model and suggested a methodology of estimating the heat input efficiency through a comparison between three dimensional molten pool simulation and experiment with regard to the variable polarity GTA welding. This research is a follow-up of the previous study, and it reveals the heat input efficiency of reverse polarity arc in aluminum welding for the first time through the suggested method. As a result, the heat input efficiency of reverse polarity is 3.8 times larger than that of straight polarity in aluminum welding.