High temperature rapid reactive joining of dissimilar materials: Silicon carbide to an aluminum alloy

An effective method for bonding of silicon carbide (SiC) ceramic to 5083 Aluminum metal-alloys was developed. This method employed the concept of high-temperature rapid heterogeneous combustion reaction to joint dissimilar materials. Scaled-up welding apparatus, which can accommodate specimens of up to 5″ in diameter and 6″ in height and allow a rapid (∼10 ms) load application (up to 1000 MPa) on the joining stack during reaction, was designed and built. An exothermic mixture of titanium and carbon powders (molar ratio 1:0.4) was utilized as a joining reactive layer. Uniform crack-free bonding of SiC to 5083 Al-alloy was accomplished both without and with application of loads. SEM and focused ion beam (FIB) images revealed that ∼10 μm (without load) and ∼500 nm (with load) transitional joining layers along the interfaces were observed, respectively. Compositional and mechanical properties of joined samples were also characterized by EDS analysis and Vickers microhardness investigations.