Carbonitriding at 1050 °C in a Glow-discharge Plasma

Abstract

Carbonitriding is often preferred to carburizing because nitrogen bearing cases exhibit greater hardenability, and thus small parts made of lowcarbon steels may be oil quenched. The results reported here demonstrate that the techniques developed for highrate, hightemperature plasma carburizing may be applied to carbonitriding with comparable success. The process conditions, however, must be adjusted to ensure that neither the carbon nor the nitrogen are lost in the later stages of the carbonitriding cycle. This requires that a carbon/nitrogen plasma be maintained during both the carbonitriding and diffusion stages, and while the workpiece is cooled to < 600 °C.