Ultra-high temperature brazing of C/C composite using pure Ni as filler based on eutectic reaction

To increase service temperature of brazed C/C-C/C joint, pure nickel was used as filler in ultra-high temperature brazing based on Ni-C eutectic reaction (1326 °C). The bond seam was composed of C-rich Ni_(S.S.) matrix (FCC) and precipitating flake graphite; intimate interface and smaller contact angle (40°) confirmed good wettability; deep infiltration up to 120 μm occurred preferentially along perpendicular fibber bundle. As a result, 21.7 MPa shear strength was obtained. Fracture occurred within C/C side, rather than within bond seam or along initial interface. These results demonstrated that using pure Ni foil as filler even without strong/moderate carbide forming elements was feasible.