from the conferences organized by TANGER Ltd.
In this work, the influence of strain and strain aging parameters on the strength and low temperature toughness of low-carbon microalloyed Nb-V-Ti and Nb-Ti steels is investigated. Industrial samples of 23 mm heavy plates after TMCP (Thermo-Mechanical Controlled Processing) and additional sPWHT (subsequent Post-Weld Heat Treatment) were used for the research. Theoretical foundations of steel aging were considered, and its primary parameters antimed mechanisms were described. One of the main challenges with steels used in Arctic areas is to ensure adequate material toughness to prevent brittle fracture. Therefore, a parameter indicating the susceptibility of steels to aging was determined. The change in the basic strength properties under 5 %, 7.5 % and 10 % pre-strain was determined. Subsequent aging was carried out by heating to 250 °C for 60 minutes. Impact tests were conducted at temperatures as low as -80 °C to determine the reliability and durability of constructions, especially in Arctic conditions. The presented results have been used with a positive outcome in the certification tests for production of heavy plate products in quality categories S355MLO, S420MLO, S460MLO according to the standards EN10225-1:2019 and NORSOK M-120, including Arctic editions (Annex F).
Keywords: low-carbon steel, TMCP, heavy plates, aging, mechanical properties© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.