Coetsee, TheresaDe Bruin, Frederik Johannes2024-02-262024-02-262024-03Coetsee, T. & De Bruin, F.J. 2024, 'Nano-strand formation in CaF2-SiO2-Al2O3-MgO flux reacted at 1350 °C with Al-Ti-Fe powder : SEM analyses and gas reaction thermochemistry', Journal of Solid State Chemistry, vol. 331, art. 124547, pp. 1-14, doi : 10.1016/j.jssc.2024.124547.0022-4596 (print)1095-726X (online)10.1016/j.jssc.2024.124547http://hdl.handle.net/2263/94930DATA AVAILABILITY : Data will be made available on request.Nano-strands form in fluoride-based slag during submerged arc welding (SAW) due to the re-condensation of gas species formed at high temperatures in the arc cavity. The SAW process is complex due to gas-slag-metal reactions occurring across several reaction zones and over a wide temperature range. This complicates research on specific process aspects, such as gas formation from the oxy-fluoride slag. The objective of this work is to demonstrate that oxy-fluoride nano-strands form in molten flux reacted with Al-Ti-Fe metal powder, even at the low temperature of 1350 °C, which is much lower than SAW process temperatures of 2000 °C–2500 °C. Energy dispersive X-ray spectroscopy (EDS) analyses and thermochemical calculations provide insights into formation reactions in nano-strand formation. Thermochemical analysis clarifies the role of Al in shifting the gas phase composition to limit Ti-fluoride loss to the gas phase. These results motivate the study of gas phase reactions at relatively lower reaction temperatures to gain insights into SAW flux behaviour.en© 2024 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license.Nano-strandsSubmerged arc welding (SAW)WeldingOxy-fluorideGasSlagFluorideThermochemistryEnergy dispersive X-ray spectroscopy (EDS)Article