High manganese and aluminum steels are derivations of Robert Hadfield’s original investigations of a Fe- 13wt.%Mn-1.2wt.%C steel with high toughness and wear resistance.1 Fully austenitic cast steels with a nominal composition of Fe-30%Mn-9%Al-0.9%C are almost 15% less dense than quenched and tempered Cr-Mo steels with equivalent strengths and higher toughness. The combination of high abrasion resistance and impact toughness along with its low weight makes these steels preferable to other existing abrasive resistant steels such as AR500/500F, AR600, and AR450. Over the last decade, there have been significant studies on the wear resistant, tensile, microstructural, and surface mechanical properties. Abrasion resistance may be further improved without degrading toughness by producing a hard AlN surface coating. However research on the nitriding process is sparse. The focus of this study is to determine the growth kinetics of nitrided layers on high manganese aluminum steels.