Effect of nitrogen implantation with overlay coatings on microhardness in 4145 steel

The effect of nitrogen implantation on microhardness in 4145 steel was investigated. Practically no increase in microhardness for 10, 20 and 40 gm loads was observed in samples implanted with a dose of 6.5×10¹⁷N⁺ ions cm^?2 at 94 keV. The effect of ion-beam induced intermixing of aluminium and titanium film (400Å), due to nitrogen implantation was also studied. A noticeable increase of 15% in microhardness was observed. Annealing at temperature ∽300°C proved effective, while a decreasing trend in hardness could be observed for annealing temperatures >300°C. Furthermore, preliminary test indicated that these samples were more suitable for wear-protection.