The Paton Welding Journal, 2026, №06

2026 №06 (01)

DOI of Article 10.37434/tpwj2026.06.02

2026 №06 (03)

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The Paton Welding Journal, 2026, #6, 17-24 pages

The influence of thermal welding cycles on the structure and mechanical properties of high-hardness armour steels

V.D. Poznyakov, O.V. Korieniev

E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: korenew@ukr.net

Abstract
The influence of thermal cycles of welding on phase-structural transformations of the metal of the heat-affected zone (HAZ) of some medium-carbon alloyed armour steels of high hardness with different chemical composition has been investigated. The total mass fraction of silicon, manganese, chromium, nickel and molybdenum in steels of grade 71, ARMSTAL 500 and Ramor 500 is 6.56, 2.76 and 2.53 %, respectively. It has been established that in the overheated region of the metal of the HAZ of steels the total mass fraction of alloying elements is 2.53‒2.76 % at cooling rates W6/5 ≤ 5.0 °C/s, and a mixed bainitic-martensitic structure is formed, and in steel 71, regardless of the cooling rate, and at W6/5 > 5.0 °C/s for other steels a martensitic structure forms. It was found that depending on the change in the structure of the metal in the HAZ overheated region, its mechanical properties also change. With increasing cooling rate, the hardness and strength of the metal increase, and the ductility properties decrease. It was established that the high resistance of welded joints of the studied steels to the formation of cold cracks can be ensured, if materials used for their welding facilitate formation of an austenitic structure in the deposited metal.
Keywords: armour steels, welding thermal cycle, metal structure, mechanical properties of the metal of welded joints, cold cracks

Received: 23.03.2026
Received in revised form: 05.05.2026
Accepted: 26.06.2026

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Suggested Citation

V.D. Poznyakov, O.V. Korieniev (2026) The influence of thermal welding cycles on the structure and mechanical properties of high-hardness armour steels. The Paton Welding J., 06, 17-24. https://doi.org/10.37434/tpwj2026.06.02

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