Influence of expansion level on base metal mechanical properties of welded straight seam L450M steel pipes

Keywords

welded straight-seam pipes, low-alloyed pipeline steel, level of pipe expan¬sion, mechanical characteristics, impact toughness.

Cite as

Dmytrakh I. M., Syrotyuk A. M., Ovsyanykov V. V., and Leshchak R. L. Influence of expansion level on base metal mechanical properties of welded straight seam L450M steel pipes. Physicochemical Mechanics of Materials. 2025. 61(6), 65-69.

https://doi.org/10.15407/pcmm2025.06.065

Abstract

The technological operation of expansion in the range of e = 0–1.2% has a negligible effect on the standard mechanical characteristics of the base metal of straight-seam welded pipes made of L450M steel. The tensile strength practically does not change, and the yield strength decreases by approximately 6% in comparison to the base metal of the unexpanded pipe. At the same time, the relative elongation and relative area reduction decrease by 6–8% with an increase in the expansion level. It is found that the impact toughness KCV of the base metal in straight-seam welded pipes is more sensitive to changes in the expansion level, and at e = 1.2% it increases by approximately 11% compared to the unexpanded pipe.

References

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