South Ural State University has introduced a new welding technology based on the use of a eutectic high-entropy alloy (EHEA). This method was developed by Tushar Sonar, Senior Research Fellow at the Department of Welding Engineering of South Ural State University.
Development of modern high-efficiency power units requires welding two dissimilar types of steel: heat-resistant martensitic steel on one side and corrosion-resistant austenitic steel on the other. This combination allows power unit components to withstand extremely high temperatures while ensuring long service life.
However, conventional welding techniques in such cases often lead to carbon diffusion, resulting in the formation of weakened zones in the welded joint.
The SUSU research team applied an eutectic high-entropy alloy as an interlayer during robotic activated gas tungsten arc welding (A-GTAW) using a tungsten electrode in a shielding gas environment with activated flux.
As a result, the weld joints demonstrated reduced brittleness, while tensile testing showed excellent mechanical performance.
“This work represents a fundamental step towards increasing the service life and safety of critical power plant components, such as boilers and steam pipelines. By controlling the weld metal composition using a high-entropy alloy, we can purposefully tailor joint properties for operation under extreme temperature and stress conditions. This research opens the way to the development of more reliable and efficient energy systems,” explained project leader Tushar Sonar.
The discovery made by Tushar Sonar is a significant breakthrough in welding technologies that are critically important for the advancement of the power-engineering sector.
“This research is an excellent example of the SUSU’s focus on fundamental science combined with industrial application,” said Mikhail Ivanov, Acting Head of the Department of Welding Engineering. “We are not merely improving welding techniques — we are offering a materials-level solution that extends equipment service life and enhances reliability and safety.”
The research results have been published in leading international journals, including Journal of Materials Processing Technology (Top 5%, Q1, https://doi.org/10.1016/j.jmatprotec.2025.118873) and Metallurgical and Materials Transactions A (Q1, https://doi.org/10.1007/s11661-025-08034-6).
This study (grant No. 24-29-20141) was carried out with financial support from the Russian Science Foundation and the Chelyabinsk Region within the frameworks of the projects competition “Conducting Fundamental Scientific Research and Exploratory Research by Individual Scientific Groups” in 2024–2025, and was implemented as part of the Priority 2030 strategic academic leadership program.