2018 №10 (01) DOI of Article
2018 №10 (03)

The Paton Welding Journal 2018 #10
TPWJ, 2018, #10, 9-13 pages
Influence of thermal cycle of welding on structure and mechanical properties of haz metal in high-strength steel produced by controlled rolling
Journal                    The Paton Welding Journal
Publisher                 International Association «Welding»
ISSN                      0957-798X (print)
Issue                       #10, 2018 (December)
Pages                      9-13
V.D. Poznyakov, A.V. Zavdoveev, S.L. Zhdanov and A.V. Maksimenko
E.O. Paton Electric Welding Institute of the NAS of Ukraine 11 Kazimir Malevich Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua

At present there is a tendency to develop high-strength alloyed steels with yield limit of more than 590 MPa, in which heat treatment (quenching and tempering) is replaced by the process of controlled rolling with subsequent accelerated cooling. Application of technologies of welding such steels is now based only on recommendations of the manufacturer of metal and welding consumables, as well as on carbon equivalent. Considering that the new generation of steels, including alform 620M, was produced due to complex application of both microalloying and thermomechanical treatment with subsequent accelerated cooling, the obtained properties can be lost as a result of softening during processing stages, associated with steel heating. As the level of the change of mechanical properties of HAZ metal determines steel weldability, the influence of thermal cycles of welding on the properties and structure of HAZ metal in high-strength steel alform 620M is considered at the first stage of investigations. Performed investigations revealed that optimum combinations of mechanical properties and structure can be achieved at the rate of cooling of welded joint HAZ metal higher than 25 °C/s. 10 Ref., 2 Tables, 4 Figures.
Keywords: high-strength steel, controlled rolling, thermal cycles of welding, heat-affected zone, structure, properties
Received:                19.07.18
Published:               18.12.18

1. Musiyachenko, V.F., Mikhoduj, L.I. (1987) Arc welding of high-strength alloyed steels. Moscow, Mashinostroenie [in Russian].
2. Gavrilov, D.S., Makhnenko, O.V. (2016) Prediction of welding strains of rotor wheel of blower HP-7500 in arc and laser technologies of welding. In: Proc. of 7th Int. Conf. on Laser Technologies in Welding and Materials Processing (14–18 Sept. 2015, Odessa, Ukraine), 14–20.
3. Ragu Nathan S., Balasubramanian, V., Malarvizhi, S., Rao, A.G. (2015) Effect of welding processes on mechanical and microstructural characteristics of high strength low alloy naval grade steel joints. Defence Technology, 11, 308–317. https://doi.org/10.1016/j.dt.2015.06.001
4. Ufuah, E., Ikhayere, J. (2013) Elevated temperature mechanical properties of butt-welded connections made with high strength steel grades S355 and S460M. In: Proc. of the Int. Conf. on Design, Fabrication and Economy of Metal Structures (24–26 Apr. 2013, Miscols, Hungary). Ed. by K. Jarmai, J. Farkas, Springer, 407–412. https://doi.org/10.1007/978-3-642-36691-8_62
5. Nazarov, A., Yakushev, E., Shabalov, I. et al. (2014) Comparison of weldability of high-strength pipe steels microalloyed with niobium, niobium and vanadium. Metallurgist, 7, 9–10, 911–917. https://doi.org/10.1007/s11015-014-9821-6
6. Zhixiong Zhu, Jian Han, Huijun Li, Cheng Lu (2016) High temperature processed high NbX80 steel with excellent heataffected zone toughness, Materials Letters, 163, 171–174.
7. Dongsheng Liu, Qingliang Li, Toshihiko Emi (2011) Microstructure and mechanical properties in hot-rolled extra high-yield-strength steel plates for offshore structure and shipbuilding. Metallurgical and Materials Transactions А, 42, 1349–1361. https://doi.org/10.1007/s11661-010-0458-1
8. Natschläger M., Egger R., Kapl S.A. (2015) Thermomechanically rolled heavy plates for penstocks. Hydropower, 1, 114–118. https://doi.org/10.1007/s35147-015-0528-9
9. (2011) Technical terms of delivery for heavy plates. Highstrength and ultra-highstrength thermomechanically rolled fine-grain steels.Voestalpine Grobblech GmbH, Austria.
10. Zavdoveev, A., Pozniakov, V., Rogante, M. et al. (2017) Weldability of S460M high strength low-alloyed steel. In: Proc. of 7th Int. Conf. on Mechanical Technologies and Structural Materials MTMS2017 (21–22 Sept. 2017, Split, Croatia). Ed. by S. Jozić, B. Lela. Croatian Society for Mechanical Technologies, Split, Croatia, 163–166.