Automatic Welding, 2020, №06



2020 №06 (03)

DOI of Article 10.37434/as2020.06.04

2020 №06 (05)

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Avtomaticheskaya Svarka (Automatic Welding), #6, 2020, pp. 23-30

Influence of low-temperature tempered structure and properties of welded joints of high-strength steel 30Kh2N2MF

O.A. Gaivoronsky, V.D. Poznyakov, O.M. Berdnikova, T.O. Alekseenko, O.S. Shyshkevych

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

The results of investigations of infl uence of low-temperature tempering on structural changes, physical and mechanical properties of HAZ metal and crack resistance of welded joints of a high-strength medium-carbon alloy steel 30Kh2N2MF are given. It is shown that the use of a low-temperature tempering is absolutely necessary during welding of products with low-alloy materials, which signifi cantly increases the crack resistance of welded joints. During welding of joints with high-alloy materials in the hardened metal, in the tempered HAZ metal a relatively more ductile and less stressed structure is formed, in which the maximum level of stresses is lower than that which can be achieved after thermal tempering of welded joint with a low-alloy weld. Therefore, the level of crack resistance of welded joints is suffi ciently high in any case and there is no need to use lowtemperature tempering for it. This is an unnecessary technological operation that does not signifi cantly aff ect the reliability during operation of products, but only increases their cost. 13 Ref., 4 Tabl., 6 Fig.
Keywords: high-strength steel, welded joints, low-temperature tempering, structure, properties, crack resistance

Received: 12.05.2020

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