This paper studies the formation of composites using a CO2 laser machine for rapid prototyping fabrication. In this process, Cu-Ti-C and Cu-Ni-Ti-C powder mixtures were milled before laser scanning. The ball-milled powder mixture was layered and scanned under the laser beam. Formation of in situ TiC was detected after laser scanning. With addition of Ni, both the microstructure structure and surface quality of the laser-fabricated parts can be improved because of the improved melting of Cu and wettability of Cu with in situ TiC.