Application of Complex Thermochemical Treatment for Reinforcing High-Strength Precipitation-Hardening Heat-Resistant Steel Microalloyed with REM

Resumo

Results of a complex thermochemical treatment of test specimens from different heats of a novel high-strength heat-resistant precipitation-hardening steel microalloyed with REM are presented. The optimum chemical composition of the steel is determined with the aim to provide precipitation hardening after vacuum carburizing. In the process of finishing nitriding in glow discharge the surface hardness of the new steel increases substantially at inconsiderable decrease in the hardness of the core. The developed modes of complex thermochemical treatment exclude the appearance of such flaws as grain boundary net and excess retained austenite.