Joining of SiC Fiber‐Bonded Ceramics using Silver, Copper, Nickel, Palladium, and Silicon‐Based Alloy Interlayers

SiC fiber‐bonded ceramics, SA ‐Tyrannohex ^® , ( SA ‐ THX ) with perpendicular and parallel fiber orientations were brazed using Ag‐, Ni‐ and Pd‐base brazes, and four Si–X (X: Ti, Cr, Y, Ta) eutectics. Outcomes were variable, ranging from bonded joints through partially bonded to un‐bonded joints. Prominent Ti‐ and Si‐rich interfaces developed with Cusil‐ ABA , Ticusil, and Copper‐ ABA and Ni‐ and Si‐rich layers with MBF ‐20. Stress rupture tests at 650 and 750°C on Cusil‐ ABA ‐bonded joints revealed a temperature‐dependent behavior for the perpendicular joints but not for the parallel joints with failure occurring at brazed interface. Higher‐use temperatures can be targeted with eutectic Si–Ti and Si–Cr alloys.