Synergistic strengthening of Al matrix composites by in situ pyrolysis of C and precipitation of nanophases

Owing to inadequate interface contact between carbon and aluminum, enhancing the Al/C interface is crucial for the fabrication of high-performance Al matrix composites. This study selected polyvinyl butyral (PVB) with excellent dispersion properties as the carbon source, simultaneously introducing silver to achieve synergistic reinforcement between silver and carbon in Al matrix composites, offering a novel reinforcement approach for Al matrix composites. The Al–16Ag–C composite is fabricated through the in situ pyrolysis of PVB followed by hot-pressing sintering. Subsequently, the effect of temperature on the microstructural evolution and mechanical properties of the composite is investigated. Microstructural characterization demonstrates the formation of two alloy phases, namely Ag 2 Al and Al 4 C 3 , within the Al–16Ag–C composite. The alloy phases, distributed at the grain boundaries, enhance the material’s strength by impeding dislocation motion, increasing dislocation density within the matrix, and limiting grain growth. The Al–16Ag–C composite, sintered at 630 °C, exhibits a remarkable ultimate tensile strength of 481 MPa and an elongation of 16.84%, representing a significant enhancement compared to pure Al.