Effects of Thermal Treatment on Welding Joints of EP823-Sh and EP302M-Sh Steels

5/18/2026 2026 - #02 Nuclear Materials

Ponimash A.V. Gibadullin R.H. Kudashov D.V. Orlov Yu.A. Dvoriashin A.M. Plaksin O.A.

https://doi.org/10.26583/npe.2026.2.14

Dissimilar welded joints between the ferritic-martensitic steel EP823-Sh and the austenitic steel EP302M-Sh, both are candidate structural materials for reactors with heavy liquid metal coolant, have been fabricated by manual argon arc welding using Sv-03Kh14N8S3BU filler wire. As a result of technological experiments and materials structure investigations, it has been shown a possibility of fabrication of welds with the austenitic-ferritic microstructure, which is favorable for preventing hot cracking formation during welding. After welding, silicon and chromium, necessary elements for corrosion resistance of the welded joints in liquid heavy metal coolants, remain in the weld metal. A combination of low-temperature tempering, which softens martensitic transformation, with subsequent step annealing treatment has been proposed for post weld heat treatment of welded joints of EP823-Sh and EP302M-Sh steels. The combined heat treatment provides an alternative to the conventional high-temperature tempering of EP823-Sh steel, with is used in production of crack-resistant and brittle-fracture resistant welded joints of EP823-Sh steel.

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structural steels heavy liquid metal coolant welded joints thermal treatment microstructure

Link for citing the article: Ponimash A.V., Gibadullin R.H., Kudashov D.V., Orlov Yu.A., Dvoriashin A.M., Plaksin O.A. Effects of Thermal Treatment on Welding Joints of EP823-Sh and EP302M-Sh Steels. Izvestiya vuzov. Yadernaya Energetika. 2026, no. 2, pp. 213-223; DOI: https://doi.org/10.26583/npe.2026.2.14 (in Russian).