Investigation of the structure and properties of surface composite layers on multi-alloyed steels

• Published in: E3S web of conferences 2023-01, Vol.413, p.2015
• Main Authors: Ishmametov, D. A., Pomelnikova, A. S., Fomina, L. P., Karpukhin, S. D.
• Format: Article
• Language: English
• ISSN: 2267-1242; 2267-1242
• DOI: 10.1051/e3sconf/202341302015

In this work were studied the structures and properties of surface composite layers obtained by chemical-thermal treatment and combined chemical-thermal treatment, combining liquid-free electrolysis-free boriding with gas nitriding. The properties of surface composite layers on steels with different alloys are analyzed depending on various parameters of chemical-thermal treatment. The study showed that, during boriding, phases of iron borides FeB, Fe2B are formed on the surface of the samples, and their volume ratio strongly depends on the degree of steel alloying. A strong effect of carbon on the morphology of surface layers was revealed. Finely dispersed strengthening particles were found in the borated layers on the VKS-5 steel, large superhard particles on the Ch12MF steel near the borated layers. The study of the microstructure of the composite layers showed that during gas nitriding, a layer 80 μm in size is obtained, which penetrates deep into the borated layer. The study of the properties of surface layers showed that carbon has the greatest influence on the formation of borated layers. The resulting composite layers are characterized by reduced microbrittleness and increased corrosion resistance.