Optimization of Application Techniques for Quenched and Tempered Steel-S550Q
Authors
-
Engineering Workshop, Larsen & Toubro Limited, Kanchipuram ,IN
K. Prakash -
DGM-Larsen & Toubro Limited, Kanchipuram ,INR. Kumar
-
DGM-L&T Construction, Larsen & Toubro Limited, Kanchipuram ,INM. V. Venkatesan
DOI:
https://doi.org/10.22486/iwj/2019/v52/i2/181776Keywords:
S550Q, EN 1011-2, Thermal Cutting, Welding, Stress Relieving, ASME SEC-IX (2015), EN ISO15614.Abstract
EN10025-6 S550Q is high strength steel classified under quenched and tempered (Q&T) manufacturing technique. S550Q is specially designed and used by the authors for welded steel structures for the purpose of heavy lifting and lowering. The entire processing techniques like cutting, edge preparation, welding, and bending are of major importance to the consistency of fabricated structure. This study comprises of introduction to HSS-S550Q and addresses various important variables by practically. The following main factors are taken to consideration heat input during cutting, edge preparation, and welding, cooling cycle, Hydrogen induced cracking (HIC). Stress Relieving (SR) is mandatory after weld fabrication. The first was to establish a need for SR to achieve desirable weldment properties. SR has been reported to have Complementary benefits such as tempering of WM and HAZ regions, and allowing the effusion/diffusion of hydrogen away from the weld region. Bend testing of cross-weld samples was used to qualify the ductility of the weldment before and after SR. In addition, impact, tensile and hardness properties, microstructures were quantified before and after SR.
References
Basu B and Raman R (2002); Microstructural variations in a high-strength structural steel weld under isoheat input conditions, Welding Journal, 81, pp. 239- 248.
Porter D (2006); Development in hot-rolled high-strength steel, Nordic Welding Conference 06 on New Trends in Welding Technology, Tampere, Finland.
Pisarski HG and Dolby RE (2003); The significance of softened HAZs in high strength structural steels, Welding in the World, 47(5/6), pp. 32-40.
Umekuni A and Masubuchi K (1997); Usefulness of under matched welds for high-strength steels, Welding Journal, 76(7), pp. 256-263.
Wang J, Li Y and Liu P (2003); Effect of weld heat input on toughness and structure of HAZ of a new super-HSS, Material Science, 26(3), pp. 301-305.
Magudeeswaran G, Balasubramanian V, Madhusudhan Reddy G and Balasubramanian TS (2008); Effect of welding processes and consumables on tensile and impact properties of high strength quenched and tempered steel joints, Journal of Iron and Steel Research International, 15, pp. 87-94.
Shi Y and Han Z (2008); Effect of weld thermal cycle on microstructure and fracture toughness of simulated heat-affected zone for a 800 MPa grade HSS, Journal of Materials Processing Technology, 207, pp. 30-39.
