A novel brush surface structure of SiCf/SiC composites designed for brazing improvement

Abstract The brush surface structure of SiCf/SiC has been designed to obtain the robust SiCf/SiC-alloy joint by reducing the residual stress and improving interface bonding. SiC fibers are exposed through thermal corrosion at a low temperature, forming the transition layer of SiC fiber-reinforced AgCuTi. The transition layer replaces the original plate reaction layer, which increases the joining area effectively and forms the 3D network of the reaction layer. The crack propagation is hindered, and SiC fibers increase the interfacial bonding. The residual stress is reduced by decreasing the property mismatch between SiCf/SiC and alloy with this transition layer. All these improvements contribute to the high shear strength. The shear strength of joints reached 41.4 MPa with the transition layer of 67 μm, twice higher than that of original joints of 20.7 MPa.