Modern Problems of Materials Science

Structure and Mechanical Properties of Heat‑Resistant Steel Restored after Long‑Term Operation in a TPP Steam Pipeline

Ivan Tsybailo1, Halyna Krechkovska1,2

1. Karpenko Physico-Mechanical Institute of NAS of Ukraine
2. Lviv Polytechnic National University, Ukraine

https://doi.org/10.15407/msse2025.01.117

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Keywords

heat-resistant steel 12Kh1MF, mechanical properties, grain size, degradation, restorative heat treatment, steam pipelines

Abstract

The paper presents the results of restoring the structure and mechanical properties of long-term operated 12Kh1MF steel from a TPP steam pipeline bend. A modified heat treatment regime involving double normalization and tempering was proposed. It ensured grain refinement, redistribution of carbides, recovery of hardness, ductility, and impact toughness, providing a significant improvement of the steel performance after long-term operation.

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