Process for carbonitriding steel.

摘要

Process for carbonitriding a steel comprising: 0.75 - 1.1 % by weight of C; up to 1.0 % by weight of Si; less than 0.015 % by weight of P; up to 0.5 % by weight of Mo; up to 1.2 % by weight of Mn; 0.5 - 2 % by weight of Cr, the remainder being Fe, by exposing it at elevated temperatures to an atmosphere comprising at least carbon monoxide, hydrogen, nitrogen and added ammonia. This is carried out by exposing it, between 780 and 900 DEG C, for from 1 to 10 hours, to an atmosphere comprising at least carbon monoxide, hydrogen and ammonia with a carbon activity between 0.90 and 1.10 and a nitrogen potential between 0.10 and 0.60 % N.