Chemical heat treatment of steels with super-equilibrium nitrogen concentration

Authors: Goncharevskaya D.A.
Published in issue: #8(49)/2020
DOI: 10.18698/2541-8009-2020-8-636
Category: Metallurgy and Science of Materials | Chapter: Metal Science, Thermal Processing of Metals and Alloys
Keywords: steels of the martensitic class, super-equilibrium concentration of nitrogen, chemical heat treatment, vacuum nitriding, vacuum carburizing, diffusion layer thickness, carbides, nitrides
Published: 07.09.2020

The paper presents the results of studies of 5KhNM type martensitic steel, in which part of the carbon is replaced by nitrogen with various super-equilibrium concentrations. The regularities of the diffusion saturation of the surface layers of steels with carbon are established depending on the saturation time and the initial nitrogen content. Data on the structure and properties of steels in the initial state and after chemical-thermal and heat treatment are presented. The analysis is carried out of the saturation kinetics of steels during vacuum carburizing and vacuum nitriding. It is shown that the use of chemical-thermal treatment makes it possible to more fully realize the potential of steels containing a super-equilibrium nitrogen concentration.

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