Abstract
Ni60-NB-Ag was firstly used to fabricate composites to increase the wear resistance of TA7 (Ti-5Al-2.5Sn) titanium alloy surface by means of a laser melted deposited (LMD) technique. Experimental results revealed that a large quantity of the interdendritic lamellar eutectics, the nanoscale particles (NP), and the amorphous structure were formed in such composites. During an LMD process, great amounts of Ag were released from the pre-placed layer, which increased the number of the nucleation points, favoring the formation of a fine microstructure and also the NP. However, too high Ag content led the micro-cracks to be produced. Compared with a TA7 substrate, an improvement of the wear resistance was observed for such LMD composites.

Key words
metal-matrix composites, surface properties, laser technique, nano-materials

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