Effect of interfacial stability on microstructure and properties of carbon fiber reinforced aluminum matrix composites

In order to explore the effect of interface stability between carbon fiber and matrix on the microstructure and properties of carbon fiber reinforced aluminum-matrix (Cf/Al) composites, Cf/Al composites were prepared with different interface coatings (Ni coating, Cu coating and TiC coating). The diffusion model of coatings in Al melt was established and calculated, and the results were compared. The calculation results show that the Ni coating and Cu coating are prone to diffusion in the Al matrix, while the TiC coating can stably exist between the Al matrix and the carbon fiber. The microstructure of Cf/Al composites prepared by different coatings was studied experimentally. When the coating is prone to diffusion in the Al melt, the coating will continuously dissolve and fall off during the preparation of the composite. At this time, due to the instability of the interface, it is easy to produce a large number of Al4C3 brittle phases at the interface. The tensile testing results show that the strength of the Cf/Al composites prepared by stable TiC coating is the highest, and it is 41% higher than that prepared by the easily diffused Cu coating under the same conditions, which will be beneficial to the improvement of the strength of the composites.