IN SITU NITRIDATION OF TITANIUM USING LENS (TM)

Research is focused on remelting the surface of a Ti substrate in a nitrogen rich environment using a commercial laser engineered net shaping (LENS (TM)) technique, leading to in situ formation of titanium nitride on the surface of titanium. The titanium nitride layer show higher hardness and wear resistance compared to Ti. By optimizing the laser parameters, surface hardness could be increased by a factor of similar to 15, while the wear damage decreased by a factor of similar to 12. Characterization techniques employed include electron microscopy and x-ray diffraction. The microstructure at the surface shows a dendritic coating with an interface of alpha-Ti needles in the remelted region.