The Paton Welding Journal, 2022, №05



2022 №05 (05)

DOI of Article 10.37434/tpwj2022.05.06

2022 №05 (07)

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The Paton Welding Journal, 2022, #5, 40-45 pages

Structure and properties of electroslag welded joints of VT6 titanium alloy

I.V. Protokovilov, V.O. Shapovalov, V.B. Porokhonko, S.G. Hrygorenko

E.O. Paton Electric Welding Institute of the NAS of Ukraine 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua

Abstract
The paper presents the results of investigations of the quality of electroslag welded joints of 100 mm plates from VT6 titanium alloy. Investigations included X-ray inspection, chemical and gas analysis, optical metallography, mechanical tensile and impact toughness tests, as well as fractographic analysis. X-ray inspection and optical metallography of the welded joint showed absence of surface and inner defects in the weld metal and HAZ. Gas analysis of the weld metal demonstrated its correspondence to standard requirements to VT6 alloy. Ultimate strength of weld metal was equal on average to 90 % of base metal strength, and impact toughness (KCU) was 1.6 times higher than in the base metal. Fractures of metal of the weld and HAZ were of transcrystalline mode of a mixed type, with areas of both ductile and brittle fracture. It is shown that the welded joint mechanical properties are determined, primarily, by the size of grains and microstructure of the weld metal and HAZ, forming under the conditions of a low cooling rate and a high heat input, characteristic for electroslag welding process.
Keywords: VT6 titanium alloy; electroslag welding; welded joint; structure; mechanical properties; fracture mode

Received: 21.04.2022
Accepted: 08.08.2022

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