Achieving SiC joints with outstanding high-temperature property via flash brazing using FeCoCrNiCu high-entropy alloy

In this paper, the “flash brazing” of SiC is successfully achieved using FeCoCrNiCu alloy in air for seconds at an ultra-low furnace temperature of 400 ℃. The interface temperature reaches over 1000 ℃ in 1 s at an ultra-fast rate via the electric field assistance. The reaction layer of the joint consists mainly of Cr23C6 and the silicides of Fe, Co, Ni, and Cu. With the increase of brazing holding time, Cu gradually precipitates from the alloy, and the shear strength of the joints first increases and then decreases. The maximum strength value is 80 MPa at the test temperature of 800 ℃. This approach could help significantly improve the efficiency of ceramic bonding and achieve low-temperature joining for high-temperature applications.