The parameter optimization and mechanical property of the honeycomb structure for Ti2AlNb based alloy

In this paper, the parameter optimization and the mechanical property of the honeycomb structure fabricated by superplastic forming/diffusion bonding (SPF/DB) process for Ti2AlNb based alloy were investigated. The uni-axial tensile test was carried out at different temperatures and strain rates. The results showed that the maximum elongation was 236 % at 970℃/0.0003s−1 and the strain rate sensitivity coefficient was 0.3. The mechanical model of the face sheet and core sheet forming was established and the forming process of the structure was analyzed by the finite element method(FEM). The FEM results showed that the grooves on the surface of the honeycomb structure gradually faded and disappeared with the width of the bonding joints increasing. And the honeycomb structure with the bonding width of 10mm was flexible and successfully fabricated. Finally, the thickness distribution of the structure was measured and it was consistent with the FEM results. The obvious microstructure evolution resulted in the reduction of tensile property. The compressive property of this structure in experiment and in FEM was investigated. The compressive strength of experimental test was 7.7MPa and that of the FEM was 6.6MPa, respectively.