A two-step process involving, the pre-metallization of the SiC ceramic by Ag-Cu-Ti foil and the Al based filler alloy was developed to join 2219 aluminum alloy and the metallized SiC. The composition of metallized SiC layer was investigated. The effect of metallization temperature on the microstructure and mechanical properties of the joint was analyzed. The brazing process showed that Al from the brazing filler and 2219 substrate reacted with Ag-Cu-Ti alloy to form intermetallic compounds. Al 3 Ti, Al 2 Ag and Al 2 Cu were detected in the joint. Ti 5 Si 3 , TiC and Ti 3 SiC 2 compounds were found adjacent to the reaction layer of the Ti and SiC. With increasing of metallization temperature, the shear strength of joint first increased and then decreased. The joint shear strength reached 16.0 MPa when the pre-metallization temperature reached 1000 • C and holding time was 10 min.

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A two-step process, including the premetallization of the SiC ceramic by Ag-26.7Cu-4Ti+B 4 C and the followed brazing with the Al-based filler alloy, was developed to join 2219 aluminum alloy and the metallized SiC. The influence of metallization temperature and the B 4 C addition on the microstructure and mechanical properties of the joint was analyzed. The reaction products of Ti and B 4 C were detected in the brazing seam, such as Ti 2 B, TiC and graphite. With increasing of metallization temperature and B 4 C addition content, the shear strength of joint first increased and then decreased. The joint shear strength reached 14.0 MPa when SiC metallized with Ag-26.7Cu-4Ti+1%B 4 C at 930 • C for 10 min, which showed that appropriate addition of B 4 C in Ag-26.7Cu-4Ti metallization layer could regulate the coefficient of thermal expansion difference between 2219 aluminum alloy and SiC to relieve the residual stress and improve the shear strength of their brazed joint.