Low-Temperature Plasma Nitriding of Low- and High-Chromium Steels

Abstract

The possibility of plasma nitriding without altering the surface morphology of structural steels 30Ni2CrMoV (30ХН2МФА) and 30CrMnSi (30ХГСА) with low chromium contents and steels 03Cr11Ni10Mo2Ti (03Х11Н10М2Т-ВД) and Cr12Mo (X12M) with high chromium contents is studied at temperatures of 400–450°C. Compound layers do not form in 30Ni2CrMoV and 30CrMnSi steels upon nitriding at low nitrogen concentrations in mixtures of N2+H2, and their surface morphologies remain the same. Nitriding can be done for steels 03Cr11Ni10Mo2Ti and Cr12Mo without forming compound layers, but the surface roughness increases at both low and high concentrations of nitrogen in the working gas.