Brazing of Ti-coated SiC using a CoFeCrNiCu high entropy alloy filler via electric field-assisted sintering

Electric field-assisted sintering technology (FAST) was used to join SiC ceramic by using a CoFeCrNiCu high-entropy alloy filler. A thin Ti film was deposited on SiC surface by physical vapor deposition to reduce the residual thermal stress in the joint. The microstructure, bending strength, and bonding mechanism were systematically investigated. It was found that a discontinuous TiC layer could be formed at the interface and the interfacial reaction products changed with different brazing temperatures. A joint with a bending strength of 72 MPa was achieved at 1200 degrees C, which is 73% higher than that of the SiC brazed without Ti coating. This work provides a new insight in the interfacial design of ceramic brazing with high mechanical properties.(c) 2023 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

Electric field-assisted sintering technology (FAST) was used to join SiC ceramic with a CoFeCrNiCu high-entropy alloy filler, and a thin Ti film was deposited on the SiC surface to reduce thermal stress. The microstructure, bending strength, and bonding mechanism were systematically investigated. It was found that a discontinuous TiC layer was formed at the interface, and the interfacial reaction products varied with different brazing temperatures. A joint with a bending strength of 72 MPa was achieved at 1200 degrees C, 73% higher than that of the SiC brazed without Ti coating. This work provides new insights in the design of ceramic brazing with high mechanical properties.