Surface Modification of Ti-6Al-4V Alloy with Laser Alloyed TiN/Ti-B Ceramic Reinforced Layers
Y. Tian, X-Y. XIA, J-N. LI, M-L. Su and X-G. Sun
Laser alloying of Fe/Al/Ni/Cr-NB mixed powders on a Ti-6Al-4V alloy substrate surface formed a hard and wear resistant layer, which was well combined with metallurgy of the substrate. The microstructures of produced laser alloyed layers with the different laser process parameters were observed. It was noted that lots of rod/block-shape precipitates were dispersed uniformly in such laser alloying layers. With the increase of the scanning speed, the fine microstructure was observed; when the scanning speed was too fast, the existence time of laser molten pool became short, leading the amorphous phases to be produced. Compared with the titanium alloy substrate, the enhancements of the microhardness and the wear resistance were obtained for this laser alloying layer.
Keywords: CO2 laser, titanium alloy, Ti-6Al-4V, ceramics, powder, laser alloying, surface modification, microstructure, microhardness, wear resistance