Evaluation of mechanical properties and vacuum brazing for TiAl/GH3536 hetero-honeycomb sandwich ultrathin-walled structure

To obtain better light and higher specific tensile strength structure, hetero-honeycomb sandwich ultrathin-walled structure that consisted of TiAl face sheets and GH3536 cores was fabricated successfully. The flatwise tensile and out-of-plane compression properties of the hetero-honeycomb sandwich ultrathin-walled structure were experimentally and analytically investigated. When the brazing temperature and the holding time were increased, the dissolution of the base materials increased until the formation of a fracture in thin-wall cores and the flatwise tensile strength increased first and then decreased. At room temperature, the average tensile strength of the joints could achieve 339 MPa, when the brazing parameter was 1080 °C for 5 min. The highest average flatwise tensile strength of TiAl/GH3536 hetero-honeycomb sandwich ultrathin-walled structure was 20 MPa. The compressive strength of TiAl/GH3536 hetero-honeycomb sandwich ultrathin-walled structure was about 60 MPa, 95% higher than that of the original core. Improving the mechanical properties of TiAl/GH3536 hetero-honeycomb sandwich ultrathin-walled structure was attributed to the structural-reinforcement and material-strengthening.