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Effect of Heat Treatment on Microhardness and Fracture Resistance of the NWZ of a Welded Joint of Microalloyed Steel EH36 with Thickness 150 mm for Offshore Oil-Gas Platforms

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Metal Science and Heat Treatment Aims and scope

The microhardness, microstructure and susceptibility to brittle fracture with respect to the CTOD parameter are studied for industrial specimens of welded joints of sheet low-carbon microalloyed steel VL EH36 Z352 with thickness 150 mm after normalizing and subsequent post weld heat treatment. It is shown that the treatment affects positively the lowering of local microhardness and elevation of resistance to brittle fracture in the coarse-grained region of the near-weld zone of the studied type of welded joint.

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Notes

  1. Depending on the chemical composition of the steel.

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Authors and Affiliations

  1. NLMK DanSteel A/S, Frederiksvaerk, Denmark

    E. A. Goli-Oglu

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  1. E. A. Goli-Oglu
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Correspondence to E. A. Goli-Oglu.

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Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 1, pp. 61 – 67, January, 2019.

2Grade VL EH36 Z35 is deciphered as follows: VL denotes rating in the DNV-GL Standard; EH denotes high-strength steel with guaranteed impact toughness at –40°C; 36 is the strength category (σy ≥ 355 N/mm2, σr = 490 – 630 N/mm2); Z35 is the quality category with respect to the level of properties in the direction of the thickness (Z-test).

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Goli-Oglu, E.A. Effect of Heat Treatment on Microhardness and Fracture Resistance of the NWZ of a Welded Joint of Microalloyed Steel EH36 with Thickness 150 mm for Offshore Oil-Gas Platforms. Met Sci Heat Treat 61, 64–69 (2019). https://doi.org/10.1007/s11041-019-00377-3

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  • DOI: https://doi.org/10.1007/s11041-019-00377-3

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