Influence of Addition of Fe₂O₃ and CaO on the Performance of Manual SHS Welding Slag

Abstract:

Fe₂O₃、CaO have been added into the combustion system of manual SHS welding as slagging elements and the effects of their addition have been studied. Results showed that the combustion velocity and the adiabatic combustion temperature both became lower as the amount of the additives increased. The additives have dropped the density and the solidification temperature of the slag, which accelerated the separation of the slag and gas from the weld pool. (0.2~2.0) g of Fe₂O₃ and (0.2~1.2) g of CaO have been added into the rod. Experiments showed that the appropriate added amounts of Fe₂O₃ and CaO for each combustion weld rod were 1.2g and 0.6g respectively. The weld slag was honeycomb, brittle and easy to be removed from the weld metal. Analysis of the microstructure and composition showed that the matrix of the weld slag was glass, with some ceramics distrabuting on it. The ceramics had high content of Al₂O₃, which was created in the combustion reaction. The matrix of the weld alloy was α-Cu solid solution, on which a second phase with high content of Fe precipitated. There were no non-metallic inclusions in the weld metal ultimately. The weld joint had favorable mechanical performance, which tensile strength reached 400MPa, that fulfil the requirement of emergency welding.

• Periodical: Key Engineering Materials (Volume 697)
• Pages: 741-744
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.697.741
• Online since: July 2016
• Authors: Zhi Zun Li*, Feng Qi Han, Li Ming Sun, Xiao Feng Han, Wen Tong Xin
• Keywords: Manual SHS Welding, Performance of Weld Slag, Slagging Elements, Weld Slag

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