Fabrication of silicon carbide coating on mullite fiber-reinforced mullite matrix composite via dip-coating

Silicon carbide (SiC) coating was fabricated on mullite fiber using polycarbosilane as SiC precursor. The concentration of the precursor solution and the dip-coating cycle were considered variables to determine optimum amounts. Results showed that the SiC coating prepared with 0.01 mol/L SiC precursor for one impregnation cycle was uniform and thin. It had a thickness of 62.2 nm, which completely covered the mullite fiber. This SiC coating inhibited the reaction between the fibers and the matrix. It also weakened interface bonding, thereby resulting in a toughened fracture behavior of the composite with SiC coating.