PSI - Issue 36

Valentin Ilyushenko et al. / Procedia Structural Integrity 36 (2022) 100–105 6 V. Ilyushenko, T. Maydanchuk, E. Lukianchenko, S. Kozulin, S. Marynenko / Structural Integrity Procedia 00 (2021) 000 – 000 The restored chambers were tested for tightness at a pressure of 10 atmospheres both in laboratory conditions and at the factory before installing them on the furnace. Checking of the repaired chambers in the amount of 10 items under the operating conditions of the steelmaking furnace indicates an extension of their service life by 70...90%. 4. Conclusions Based on the research carried out, the following main conclusions can be drawn: 1. The nature and causes of the formation of defects in the copper chambers of the ASF have been determined. Namely: the formation of deep cracks across the entire working surface of the samples during their operation. Along with mechanical damage, local burnout of copper on the end part of the chambers, up to through burn-throughs of the walls of the water-cooling channels as a result of the peculiarities of the operation of these parts (thermal, chemical and mechanical effects). 2. The mechanism of cracking in the end part of the chambers: selenium, which is a surface-active element with a low melting point (217°С) and a small distribution coefficient during copper crystallization, is concentrated along the grain boundaries, which leads to the effect of adsorptive decrease in plasticity and strength. The presence of tensile stresses associated with the thermal deformation conditions of the operation of the copper chambers, as well as the coarse-crystalline structure of cast copper, leads to the formation of microcracks, which subsequently propagate through the metal thickness. 3. A technology has been developed for repairing ASF copper chambers by helium-arc welding using a special metal-cored wire, which makes it possible to extend the service life of the chambers by 70...90%. References Anoshin, V., Ilyushenko, V., 2018. Influence of surface-active elements on the formation of crystallization cracks. Automatic welding 10, 17-26. Belkovsky, A., Katz, Ya., Krasnyansky, M., 2003. The current state and trends in the technology of steel production in particle board and their designs. Bulletin "Ferrous Metallurgy" 3, 72-88. Ilyushenko, V., Lukyanchenko, E., 2013. Welding and surfacing of copper and copper alloys, 396. Ilyushenko, V., Maidanchuk, T., Bondarenko, A., Lukianchenko, E., Udartseva, T., Andreichuk, D., 2019. Restoration of end part of copper gas oxygen chambers of arc steel-melting furnaces. Electrometallurgy Today 4, 38-43. Massalsky, T., 1986-1987. Binary Alloy Phase Diagrams. V: 1-2. American Society for Metals. Ohio: Metals Park, 22-24. Osintsev, O., Fedorov, V., 2004. Copper and copper alloys. Domestic and foreign brands: Handbook, 336. Smiryagin, A., Smiryagina, H., Belova, A., 1974. Industrial non-ferrous metals and alloys, 488. 105