Importance of Plasma Nitriding Process- A Case study of 40Cr4Mo3 Material

Abstract

Everydaya lot of machineries, involves various relative motions between the mating parts and there is a need to improve the surface to make it to face the severe working conditions. The ductile materials are soft in nature and it is no longer good enough to meet friction and the associated wear. Hence it is recommended to go for surface improvement so as to increase hardness on the surface only and retaining the core material hardness as unaltered. For improving surfaces, Nitriding processes gives promising results. In Nitriding process the objective is to diffuse nitrogen into the metal surface to make the surface hardened. The three methods of Nitriding is available in the literature and in this paper an attempt has been made to emphasize the processes in brief for Gas Nitriding, Liquid bath Nitriding and Plasma Nitriding. Also 40Cr4Mo3 material has been nitrided and checked for energy consumed in Charpy V-notch test method. Also SEM results have been presented for confirming nitrided dispersion. Conclusions are made in favour of Plasma Nitriding for its desired environmental friendly process characteristics, stability with low temperature applications.