Thermochemically treating steel part i.e. gear train that is used in gear box, comprises performing first thermochemical enrichment process in steel with carbon and a second thermochemical enrichment process in steel with nitrogen

摘要

The method comprises: performing a first thermochemical enrichment process in a steel part with carbon at specific temperature; performing a second thermochemical enrichment process in the steel part with nitrogen at specific temperature; performing the re-austenitization of the steel part; and hardening the steel part by inducing heat. The treated steel part is cooled to avoid oxide formation on a surface of the steel part. The first and second thermochemical enrichment processes are performed at 300-700[deg] C. The re-austenitization process is carried out under a controlled atmosphere. The method comprises: performing a first thermochemical enrichment process in a steel part with carbon at specific temperature; performing a second thermochemical enrichment process in the steel part with nitrogen at specific temperature; performing the re-austenitization of the steel part; and hardening the steel part by inducing heat. The treated steel part is cooled to avoid oxide formation on a surface of the steel part. The first and second thermochemical enrichment processes are performed at 300-700[deg] C. The re-austenitization process is carried out under a controlled atmosphere in the presence of inert gas, preferably in the presence of nitrogen gas. The steel is slightly alloyed steel including 0.1-0.3 wt.% of carbon, the first thermochemical enrichment process increases the content of carbon to 0.9 wt.%, and the second thermochemical enrichment process is carried out to increase the content of nitrogen to 15 wt.%. An independent claim is included for a steel mechanical component.