Журналы →  Chernye Metally →  2022 →  №10 →  Назад

Metallology and Physics of Metals
Название Microstructure and mechanical properties of 122 mm welded joints of low-carbon microalloyed heavy plate steel after TM+ACC
DOI 10.17580/chm.2022.10.09
Автор E. A. Goli-Oglu, A. N. Filatov
Информация об авторе

NLMK DanSteel, Frederiksverk, Denmark:

E. A. Goli-Oglu, Cand. Eng., Chief Technologist, e-mail: Egoli-Oglu@yandex.com
A. N. Filatov, Metallurgical Engineer


The relevance of investigating the quality of thick-walled welded joints is explained by the increased technological complexity of manufacturing and the consistent increase in the requirements for reliability and operational durability of welded structures for critical purposes. Microstructure and mechanical properties of 122 mm thick-walled welded joints after submerged arc welding (SAW) with heat inputs of 15 and 50 kJ/cm are under investigations. The microstructural condition of critical heat-affected zones, hardness, impact energy and resistance to fatigue strength are identified, described and tested. The microalloyed steel with СEQ ≤ 0.33% used for the welded joint and produced by thermomechanical controlled process with accelerated cooling, is showing a high level of resistance to static and dynamic loads in the welded joint and is recommended for use when manufacturing critical structures with high level of reliability. The results of the study were used in the course of certification testing of VL E36 / S420ML heavy plates according to the international rules DNV-OS-B101 and TUV 305/2011/EU: System 2+ and ABS Rules Materials and Welding.

Ключевые слова Welded joint, low-carbon steel, heavy plate, thermomechanical treatment, heataffected zone, microstructure, impact test, fatigue strength
Библиографический список

1. DNVGL-CP-0243. Class Programme. Approval of Manufacturers. Rolled steel products – nonstainless steel. Oslo, 2019. 33 p.
2. DS/EN 10225-1:2019. Weldable structural steels for fixed offshore structures. Technical delivery conditions. Part 1: Plates. Brussels, 2019. 64 p.
3. Goli-Oglu Е. А. Production of structural steel heavy plates up to 100 mm by TMCP with final accelerated cooling for wind generators and bridgebuilding. Part 1. Chernye Metally. 2021. No. 5. pp. 17–22.
4. Goli-Oglu E. Heavy plates for offshore wind. Stahl und Eisen. 2022. No. 6. pp. 51–57.
5. Major Capital Project: Big Foot. 2022. Available at: https://www.chevron.com/-/media/chevron/projects/documents/BigFoot-Factsheet.pdf (accessed: 31.05.2022).
6. Bokachev Yu., Sarkits I., Goli-Oglu Е. NLMK-DanSteel: production of thick sheets and heavy plates. Metallurg. 2014. No. 5. pp. 67–70.
7. Ivanov А. Yu., Sulyagin R. V., Orlov V. V., Kruglova А. А. Formation of structure in the heat affected zone and properties of welded joints of pipe steels of X80, X90, K70 strength classes. Stal. 2011. No. 7. pp. 85–90.
8. European Standard 10225. Weldable Structural Steels for Fixed Offshore Structures. Technical Delivery Conditions. Brussels, 2009. 84 p.
9. Amanie J., Oguocha I., Yannacopoulos S. Effect of submerged arc welding parameterson microstructure of SA516 steel weld metal. Canadian Metallurgical Quarterly. 2012. Vol. 51. pp. 48–57.
10. Samokhotskiy А. I., Parfenovskaya N. G. Technology of heat treatment of metals. Moscow: Mashinostroenie, 1976. 311 p.
11. Lolla T., Babu S. S., Lalam S., Manohar M. Сomparison of simulated heat affected zone microstructures of niobium microalloyed steels subjected to multi-pass weld thermal cycles. Proceedings of the International Seminar on Welding of High Strength Pipeline Steels. CBMM and TMS. 2013. pp. 281–297.
12. Chegurov М. К., Sorokina S. А. Fundamentals of fractographic analysis of fractures of specimens from structural alloys: tutorial. N. Novgorod: NNSTU named after R. E. Alekseev, 2018. 79 p.
13. Methodical instructions. Calculations and strength tests. Classification of types of fractures of metals. RD50-672-88. Moscow, 1989.

Language of full-text русский
Полный текст статьи Получить