The Paton Welding Journal, 2019, №03



2019 №03 (01)

DOI of Article 10.15407/tpwj2019.03.02

2019 №03 (03)

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The Paton Welding Journal, 2019, #3, 11-14 pages
 
Journal The Paton Welding Journal
Publisher International Association «Welding»
ISSN 0957-798X (print)
Issue #3, 2019 (March)
Pages 11-14

Effect of reheating in multipass submerged-arc welding on delayed fracture resistance of rotor steel welded joints

V.Yu. Skulsky¹, S.I. Moravetsky¹, M.A. Nimko¹, Yu.G. Pashchenko², A.G. Kantor² and V.V. Dmytryk³

¹E.O. Paton Electric Welding Institute of the NAS of Ukraine 11 Kazimir Malevich Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua
²JSC «Turboatom» 199 Moscow Ave., 61037, Kharkov, Ukraine. E-mail: office @turboatom.con.ua
³NTU «Kharkov Polytechnic Institute» 2 Kirpicheva Str., 61002, Kharkov, Ukraine

The change in relayed fracture resistance, depending on preheating temperature and thermal effect during deposition of new beads was experimentally studied, using the Implant method, in the case of 0.25C–2CrNiMoV rotor steel joints, produced by submerged-arc welding. The nature of the change in hardness in the cross-section of quenching steel with a deposited bead was investigated, which illustrates formation of quenching and tempering areas under the influence of reheating in welding. Using critical stresses as a quantitative index, causing delayed fracture, it was shown that after reheating in welding, the cracking resistance can increase by about 1.5–2.5 times or more. Under the conditions of welding without preheating, one-time and two-time cycles of heating in welding increase the cracking resistance up to the level obtained during welding with preheating up to 150–200 °C. 9 Ref., 4 Figures.
Keywords: heat-resistant rotor steel, submerged-arc welding, quenching, reheating in welding, Implant, delayed fracture resistance
 
Received: 28.11.18
Published: 11.04.19
 

References

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