CARBONITRIDING METHOD HAVING A FINAL NITRIDATION STEP DURING TEMPERATURE DECREASE

摘要

A method for the low-pressure carbonitriding of steel parts, in particular parts used in the manufacture of automobiles comprises a heating step that includes a simple heating phase (M) followed by an initial nitridation phase (Ni) from a temperature between 700° C. to 750° C. to a temperature between 860° and 1000° C. carried out using a reduced temperature gradient relative to the simple heating phase. The method further includes alternate cementing (C1-Cn) and nitridation (N1-Nn) steps at constant temperature, wherein the final nitridation step is accompanied with a decrease in temperature immediately before quenching (T).