Authors: A.R. Mikhno, R.E. Kryukov, Yu.V. Bendre

Title of the article: Thermodynamic aspects of manganese restoration when using flux made from silicomanganese production slag

Year: 2025, Issue: 4, Pages: 41-49

Branch of knowledge: 2.5.8. Welding, related processes and technologies

Index UDK: 621.791.048

DOI: 10.26730/1999-4125-2025-4-41-49

Abstract: The processes of welding and submerging are widely used to repair metal structures, as well as to give various properties to the surfaces of products before putting them into operation. Manganese-silicon-containing fluxes play a special role among fluxes. An important role in the production of such fluxes is played by the use of various additives in their manufacture, including metallurgical man-made production waste. On the other hand, it is necessary to study the effectiveness of using these fluxes with various filler wires. To estimate the probability of redox reactions between the components of fluxes and filler wires, the thermodynamic characteristics of enthalpy, entropy and Gibbs energy of reactions under standard conditions were calculated according to tabular data. Based on the analysis of the data obtained, it can be concluded that manganese in flux oxide has the greatest oxidizing ability in combination with calcium, followed by magnesium, titanium, and aluminum in powder wire. It should be noted that with increasing temperature, the oxidizing ability of manganese oxide increases in reaction with silicon during the formation of SiO gas, and in all other cases, reducing agents lose their reducing activity as the temperature increases. According to the calculated data obtained, it can be argued that the reduction of manganese with iron is impossible in this case. The obtained results of chemical analysis confirm the reduction of manganese in welds. The results of the SEM analysis confirm the presence of manganese in the weld, which may turn into non-metallic inclusions due to the presence of MnO2 in the welding flux. It is also necessary to note a certain pattern: the more manganese is contained in the welding flux, the larger the non-metallic inclusions.

Key words: Silicomanganese slag surfacing welding flux Gibbs energy

Receiving date: 25.02.2025

Approval date: 22.06.2025

Publication date: 28.08.2025

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