Facilitating flux design process geared towards submerged arc welding via thermodynamic approach: Case study into CaF2–SiO2–Na2O–Al2O3–TiO2 agglomerated flux

Abstract

Submerged arc welding is a metallurgical process with temperature of 2000°C, during which complex chemical reactions occur. Due to an incomplete understanding of flux thermodynamic properties and welding process, experiments are required for the flux design, thereby consuming significant resources. Within this study, thermodynamic software, FactSage, is employed to facilitate the flux design subject to CaF2–SiO2–Na2O–Al2O3–TiO2 agglomerated flux. Then, experiments are performed with designed fluxes, and transfer behaviors of the essential elements have been quantified by Δ values. The measured data indicates that the thermodynamic approach proposed in present study is capable of facilitating the flux design process and developing the selection strategies for the welding materials. Additionally, the elemental transfer mechanisms have been evaluated, and assumptions made in previous studies have been discussed from the perspective of thermodynamics. The limitations of the thermodynamic approach are also given.