An efficient and low-cost Liquid silicon infiltration method to prepare SiC-coated carbon short fiber for fiber protection of Cf/SiC ceramic matrix composites

Abstract Liquid silicon infiltration (LSI) is a fast and low-cost method for the manufacturing of Cf/SiC composites. However, due to the high reactivity of LSI process, the carbon fiber is easily to be eroded by liquid silicon. A recognized solution is to coat the fiber surface with a protective layer. Here, we report a preparation method of Cf@SiC short fiber for carbon fiber protection in LSI process. First, Cf@HTC short fiber with controllable thickness (1–10 μm) and uniform Hydrothermal carbon (HTC) coating was prepared by hydrothermal method. After the first LSI, silicon carbide layers which was derived from the reaction of HTC and liquid silicon had been successfully constructed on the carbon fibers with the thickness rang form 1–3 μm. This strategy demonstrates a tantalizing possibility and promising prospect to the preparation of light and high strength Cf/SiC ceramic matrix composites with good fiber protection.