Microstructural evolution and mechanical properties of a nickel-based honeycomb sandwich

A nickel-based superalloy honeycomb sandwich was manufactured by high-temperature brazing. The microstructural evolution and the out-of-plate mechanical properties were determined for honeycomb sandwiches aged at 800 °C. The maximum tensile strength was 28.5 MPa and the compressive yield strength was 29.6 MPa for the original specimens. These parameters decreased to 24.7 MPa and 23.5 MPa for specimens aged for 10 h, to 24.9 MPa and 21.5 MPa for specimens aged for 20 h and to 26 MPa and 24.8 MPa for specimens aged for 30 h, respectively. With increased aging time the tensile elongation decreased, the intermetallic compounds and the eutectic structure in the brazing region disappeared, and the solid solution approaching the matrix gradually increased.