PSI - Issue 20

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2018) 000 – 000

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 20 (2019) 148–153

1st International Conference on Integrity and Lifetime in Extreme Environment (ILEE-2019) Investigation of forming heat affected zone of the deposited weld metal in adaptive-pulse welding in low climatic temperatures Sivtsev M.N. a , Sleptsov G.N. a, * , Harbin N.N. a , Stepanova K.V. a , Everstov M.M. a a Larionov Institute of the Physical-Technical Problems of the North of the Siberian Branch of the RAS (IPTPN), department of welding technology and metallurgy, Oktyabrskaya st. 1, Yakutsk, 677890, Russian Federation Abstract This article discusses the possibilities of forming the structure of the heat-affected zone (HAZ) in adaptive pulsed welding at low temperatures. It is determined that the use of adaptive pulsed welding allows the formation of a dispersed and uniform structure of the heat-affected zone. In order to identify the effect of current pulses on the formation of HAZ, the same technological parameters of the welding process were maintained. The results showed the possibility of determining the optimal algorithms for adaptive pulse control of welding processes, both positive and negative temperatures. Metallographic studies showed that in all deposited specimens, the weld structures have a dendritic structure: in the zone adjacent to the transition zone in the form of columnar formations, and closer to the outer surface, the dendrites have a disoriented structure. It was revealed that when using adaptive pulsed welding, the grain size in the heat-affected zone is reduced by 1.3 times both at positive and negative climatic temperatures, which undoubtedly positively affects the increase in the strength characteristics of the welded joint. 1st International Conference on Integrity and Lifetime in Extreme Environment (ILEE-2019) Investigation of forming heat affected zone of the deposited weld metal in adaptive-pulse welding in low climatic temperatures Sivtsev M.N. a , Sleptsov G.N. a, * , Harbin N.N. a , Stepanova K.V. a , Everstov M.M. a a Larionov Institute of the Physical-Technical Problems of the North of the Siberian Branch of the RAS (IPTPN), department of welding technology and metallurgy, Oktyabrskaya st. 1, Yakutsk, 677890, Russian Federation Abstract This article discusses the possibilities of forming the structure of the heat-affected zone (HAZ) in adaptive pulsed welding at low temperatures. It is determined that the use of adaptive pulsed welding allows the formation of a dispersed and uniform structure of the heat-affected zone. In order to identify the effect of current pulses on the formation of HAZ, the same technological parameters of the welding process were maintained. The results showed the possibility of determining the optimal algorithms for adaptive pulse control of elding processes, both positive and negative temperatures. Metallographic studies showed that in all deposited specimens, the weld structures have a dendritic structure: in the zone adjacent to the transition zone in the form of columnar formations, and closer to the outer surface, the dendrites have a disoriented structure. It was revealed that when using adaptive pulsed welding, the grain size in the heat-affected zone is reduced by 1.3 times both at positive and negative climatic temperatures, which undoubtedly positively affects the increase in the strength characteristics of the welded joint.

© 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ILEE-2019 organizers © 2019 T he Author(s). Published by Elsevier B.V. Peer-review under responsibility of the ILEE-2019 organizers © 2019 T he Author(s). Published by Elsevier B.V. Peer-review under responsibility of the ILEE-2019 organizers

Keywords: Adaptive pulse-arc welding; heat-affected zone; microstructure; negative temperature Keywords: Adaptive pulse-arc welding; heat-affected zone; microstructure; negative temperature

1. Introduction Improving the efficiency of arc welding and alloying processes accompanied by continuous improvement of 1. Introduction Improving the efficiency of arc welding and alloying processes accompanied by continuous improvement of

2452-3216 © 2019 The Author(s). Published by Elsevier B.V. Peer-review under responsibility of the ILEE-2019 organizers 2452-3216 © 2019 Th Author(s). Publis d by lsevier B.V. Peer-review under responsibility of the ILEE-2019 organizers * Corresponding author. Tel.: +7 (4112) 39-06-19; fax: +7 (4112) 33-66-08. E-mail address: slepzovgn@mail.ru * Corresponding author. Tel.: +7 (4112) 39-06-19; fax: +7 (4112) 33-66-08. E-mail address: slepzovgn@mail.ru

2452-3216 © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ILEE-2019 organizers 10.1016/j.prostr.2019.12.131