The effect of SiC nanowires on the mechanical properties of carbon fiber reinforced aluminum matrix composites

In this study, SiC nanowires were in-situ synthesized on carbon fibers (CF-SiC_NWs) at various thermal evaporation preparation temperatures and subsequently utilized as reinforcement in the fabrication of carbon fiber reinforced aluminum matrix composites (CF-SiC_NWs/Al) through the pressure infiltration technology. The results indicate that the presence of SiC nanowires significantly enhances the interlaminar shear strength (ILSS) of the CF-SiC_NWs/Al composites. Furthermore, with an increase in preparation temperature, the strengthening effect becomes more pronounced. The highest average ILSS of the CF-SiC_NWs/Al composite was 99.20 MPa, representing a improvement of 96.35 % improvement compared to the CF/Al composite. The bending strength increased from 358.01 MPa to 384.71 MPa, corresponding to an improvement of 8 %. This improvement is attributed to the synergistic reinforcement capability between SiC nanowires and CF. However, excessively high preparation temperatures lead to increased spacing between carbon fibers, which diminishes the reinforcement effect. The fracture mechanism of both CF/Al and CF-SiC_NWs/Al composites during shear and bending are discussed.