METHOD FOR LOW PRESSURE CARBONITRIDING USING A REDUCED TEMPERATURE GRADIENT IN AN INITIAL NITRIDATION PHASE

摘要

The invention relates to a method for the low pressure carbonitriding of steel parts in particular parts used in the manufacture of automobiles comprising: a heating step that includes a simple heating phase (M) followed by an initial nitridation phase (Ni) from a temperature between 700°C and 750° C to a temperature between 860° C and 1000° C and is carried out using a reduced temperature gradient relative to the simple heating phase; and 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 a quenching step (T).