Brazing of ZrB2–SiC–C and GH99 with AgCuTi/SiC interpenetrating network structural composite as an interlayer.

Ceramic/metal interpenetrating network structure has been proved to have a significant effect on decreasing the coefficient of thermal expansion (CTE) of the metal matrix. In our study, a AgCuTi/SiC interpenetrating network structural composite (ASINC) was fabricated through a melt infiltration method. During the infiltration process, the AgCuTi filler melted and infiltrated into a porous SiC ceramic. Wetting behavior of the AgCuTi on the porous SiC ceramic was studied. Microstructure of the ASINC was characterized. The synthesized ASINC was fabricated as an interlayer to prepare a ZrB 2 –SiC–C ceramic/AgCuTi/ASINC/AgCuTi/GH99 brazed joint. Typical microstructure of the joint brazed at 860 °C for 10 min was investigated. The effect of holding time on the microstructure and the room-temperature shear strength of the brazed joints was studied. The maximum shear strength increased by 161% compared with the case brazed with a single AgCuTi interlayer. Microstructure evolution and mechanical strengthening mechanisms of the brazed joints were discussed in detail. [ABSTRACT FROM AUTHOR]