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

Abstract

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.

Effect of the B4C particles on the brazed joints of SiC ceramics and 2219 aluminum alloy

“…It could be observed that the addition of B 4 C had a great influence on the microstructure of the joints. Cracks appeared in the base material SiC side of the joint without the addition of B 4 C as shown our previous study, 24 whereas no obvious defects were found in the brazing seam with 1 wt.% B 4 C addition as shown in Figure 10A,D. The B 4 C aggregate zone was formed in the brazing seam.…”

“…There are some cavities in the brazed seam with the metallization temperature of 960°C, the connection between 2219 aluminum alloy and the metallization layer is poor. A certain content of compounds with low thermal expansion coefficient could relieve the residual stress 24 . However, the reaction in the joint is violent at the higher metallization temperature.…”

“…And the joint of metallized SiC/2219 aluminum alloy was obtained by the brazing process as shown in Figure 2B. The schematic diagram of shear test device was shown in our previous study as shown in Figure 2C 24 . During brazing experiment, the vacuum was higher than 1 × 10 −3 Pa, and all brazing process between metalized SiC and 2219 aluminum alloy are same, so the brazing process parameters were omitted in the later analysis.…”

“…A certain content of compounds with low thermal expansion coefficient could relieve the residual stress. 24 However, the reaction in the joint is violent at the higher metallization temperature. Lots of intermetallic compounds occur in the brazing seam.…”

Formation of Cu Nanotwins on Silicon Carbide Wafers with Cr Adhesive Layer under Various Substrate Bias

“…Its intermediate thermal expansion coefficient, which lies between that of copper and silicon carbide, makes it conducive for mitigating thermal stress-induced delamination at the substrate-interface interface [24]. The novelty of this work is the evaluation of another adhesive layer Cr for the growth of nanotwins on the SiC chips, in contrast to the traditional Ti adhesive film which has been concerning due to the formation of TiC precipitates at the SiC/Ti interface, leading to an increase of the electrical resistance [25].…”