Authors: N.V. Ababkov, A.A. Pashkov, M.V. Pimonov, E.E. Levashova, A.V. Shchepetkov, A.S. Sivushkin

Title of the article: Influence of hardening mode of high-quality alloy steel on structure, mechanical, acoustic and magnetic characteristics. Part 1. Volume hardening and tempering

Year: 2024, Issue: 4, Pages: 58-69

Branch of knowledge: 2.6.1 Metal science and heat treatment of metals and alloys

Index UDK: 621.785.616

DOI: 10.26730/1999-4125-2024-4-58-69

Abstract: The relevance of the presented research is due to the need to obtain surface layers of parts with high strength and ductility. To do this, it is necessary to select the appropriate mode of volumetric hardening, which will increase the strength and use the material in question for the manufacture of parts and products that can withstand high loads. The article studies the influence of the heat treatment mode of high-quality alloy 0.38C-2Cr-1Mo-1Al steel on the structure, mechanical, acoustic and magnetic characteristics. The first part of the study examined various options for volumetric quenching, tempering and cooling. The most suitable heat treatment modes have been established, which provide the optimal combination of proof strength, tensile strength, elongation, impact strength and the ratio of granular to lamellar pearlite. The statistical processing of the results of measuring mechanical characteristics made it possible to obtain equations of the relationship between the conditional yield strength, tensile strength and hardness, which can be used to predict the mechanical properties of finished products after heat treatment. Based on the results of metallographic studies, it was established that the structure of the steel under study consists of two phases - lamellar and granular pearlite. The mechanical properties of pearlite depend primarily on the total thickness of the plates of both phases: the smaller it is, the higher the values of the tensile strength and yield strength and the lower the cold brittleness temperature, which corresponds to the considered heat treatment modes of the samples. Non-destructive testing did not show unambiguous results of correlation with mechanical properties after heat treatment, however, a relationship was revealed between impact strength and the amplitude range of the received surface acoustic wave signal. Thus, the application of the spectral-acoustic method of non-destructive testing requires further research.

Key words: volumetric hardening microstructure hardness mechanical characteristics non-destructive testing spectral-acoustic method magnetic noise intensity

Receiving date: 01.04.2024

Approval date: 25.07.2024

Publication date: 26.09.2024

CITE DOWNLOAD