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Silicon carbide reinforced aluminium matrix composites (AMCs) attracted a lot of attention owing to their low density, high specific strength and specific stiffness, and good wear resistance. Selective laser melting (SLM) technique has been widely used in the preparation of complex structural product with high precision, short production cycle and low cost. In this paper, silicon carbide (SiC) powders and aluminium (Al) powders were mixed together firstly with a weight ratio of 15:85 and then used to prepare AMCs by SLM technology. The effects of laser power on the microstructures, microhardness and flexural strength of formed AMCs were studied. The results show that the relative density, microhardness and flexural strength of the as-prepared samples can be improved with increasing the laser power. Meanwhile, the samples prepared at higher laser power exhibit lower friction coefficient.

B4C-particle-reinforced Al (B4Cp/Al) composites are widely used in various areas, e.g., armors, electronic packaging and fuel storage, owing to their several outstanding properties including high specific rigidity, excellent wear resistance and light weight. Selective laser melting (SLM) is favored in manufacturing complex components because of its high raw material utilization rate and high efficiency. In this work, a B4Cp/Al composite was successfully synthesized by SLM, and the effects of one of the most important parameters, scanning speed (100–700 mm/s), on the phase composition, density, microhardness and tribological properties of the samples were investigated. The microhardness, relative density and dry-sliding wear resistance of as-prepared B4Cp/Al composites were improved with the decrease in scanning speed, and the sample fabricated at a scanning speed of 100 mm/s exhibited a relative density as high as about 97.1%, and a maximum microhardness of ~180 HV0.1 (approximately six times more than that of the SLM-formed pure Al sample, 31 HV0.1), a minimum wear rate of 4.2 × 10−5 mm3·N−1·m−1 and a corresponding friction coefficient of 0.41. In addition, abrasive wear, adhesive wear and oxidation wear were found to be behind the overall wear behavior of as-prepared B4Cp/Al composites.

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