Novel duplex cathodic cage plasma nitriding of non-alloyed steel using aluminum and austenite steel cathodic cages

In this work, a duplex cathodic cage plasma nitriding (CCPN) process is performed using aluminum (pre and post treatment) and stainless steel cathodic cages. The duplex treated samples are also compared with the single treatments. The nitrided samples are analyzed with Vickers micro-hardness tester, X-ray diffraction and scanning electron microscope along with energy dispersive spectroscopy. It is found that the duplex post-aluminum CC process attains a surface hardness of ∼1124 HV; far higher than the other treated samples and previously reported in the literature. The crystal structure of post-aluminum nitrided samples shows the dominant aluminum nitride phase. The compatibility of the reported process with the existing industrial systems makes it promising for large-scale industrial uses.