Effect of metallization temperature on brazing joints of SiC ceramics and 2219 aluminum alloy

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. Al3Ti, Al2Ag and Al2Cu were detected in the joint. Ti5Si3, TiC and Ti3SiC2 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 degrees C and holding time was 10 min.