Simultaneous control of the nitrogen and carbon activities during nitrocarburising of iron

►A new method to compose nitrocarburising gas atmospheres is proposed. ►The atmosphere contains NH3, H2, CO, CO2, CH4, H2O and N2. ►It allows control of the activities of N and C at the surface of the specimen. ►A tube furnace dedicated to this method is described. ►A series of nitrocarburising has been performed using this method.