ISSN (print) 1995-2732
ISSN (online) 2412-9003

 

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DOI: 10.18503/1995-2732-2020-18-1-23-30

Abstract

State of the issue. Although it is important to know such factor as a value of plastic resistance of steel, when designing and calculating metal forming processes, it may be challenging to find information relevant for its calculation. Two main reasons may be mentioned: many calculation methods and even greater steel grades. Besides, as a rule, calculation methods and published values of numerical coefficients used in calculations vary for cold and hot forming processes. The least studied range of temperatures is approximately from 300 to 600°C. This paper is devoted to studies on plastic resistance of steel grade 32G2U in view of its functional properties. This steel grade was chosen because it is widely used in manufacturing of seamless pipes for the oil and gas industry. The characteristic feature of the studies is a common methodology used for a temperature range from room temperature to temperatures close to melting temperature. Such broad temperature range contributes to the use of the obtained results, when calculating all possible pipe manufacturing operations, such as hot working, sizing and leveling of pipes in heat treatment divisions of pipe rolling shops, forming of longitudinal welded pipes. Research methodology. To determine values of coefficients included in the equation, the authors conducted tests applying Gleeble 3800. Using the generated strain resistance curves for a temperature range of 300 to 1200°C, the authors determined values of the coefficient characterizing steel softening. For the first time, it was found that steel is softened at temperatures close to 600°С and this phenomenon was explained in terms of physics. Findings. The authors determined the reasons for steel softening at temperature close to 600°C. The test results showed a recurrent dependence to calculate a value of steel resistance considering softening in a broad range of temperatures.

Keywords

Softening, microstructure, plastic deformation, plastic resistance of steel.

For citation

Al-Khuzai A.S.O., Vydrin A.V., Shirokov V.V. Studying Plastic Resistance of Steel Grade 32G2U in a Broad Range of Temperature Change. Vestnik Magnitogorskogo Gosudarstvennogo Tekhnicheskogo Universiteta im. G.I. Nosova [Vestnik of Nosov Magnitogorsk State Technical University]. 2020, vol. 18, no. 1, pp. 23–30. https://doi.org/10.18503/1995-2732-2020-18-1-23-30

Ahmed S. O. Al-Khuzai – Postgraduate Student

South Ural State University (SUSU), Chelyabinsk, Russia. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Alexander V. Vydrin – DrSc (Eng.), Professor

South Ural State University, Deputy General Director for Research

OJSC Russian Research Institute of the Pipe Industry (RosNITI), Chelyabinsk, Russia. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Vyacheslav V. Shirokov – PhD (Eng.), Associate Professor

South Ural State University (SUSU), Chelyabinsk, Russia.

E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.. ORCID 0000-0003-1663-9362

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