04.1 - Aerospace Grade Materials, Structural Analysis, Fatigue and Damage Tolerance
EXPERIMENTAL INVESTIGATIONS ON TENSILE PROPERTIES OF ALUMINUM HONEYCOMB SANDWICH STRUCTURES WITH SINGLE-SIDED REPAIRING
B. Yan¹, G. Zhang¹, M. Tong¹, L. Li¹, D. Yu¹, S. Zhu¹, Z. Wu², H. Wang², T. Jin, China Special Vehicle Research Institute, China; ¹Nanjing University of Aeronautics & Astronautics, China ;²Nanjing University of Aeronautics and Astronautics, China
Tensile properties of single-sided panel repair(SP) and panel/core repair(SPC) of aluminum alloy honeycomb sandwich structure(AAHSS) used in civil aircraft were researched by experiments and compared with that of AAHSS without repair. Firstly, a clamp suitable for testing the tensile properties of wide-wall panels with different thicknesses was designed. Then, the failure behavior, the strain and deformation characteristics of SP and SPC structures were firstly studied by digital image correlation (DIC) technology. The results showed that the debonding of the patch and the fracture near the root were the main failure modes of the SP structure, and the strength recovery rate was 101%. A summary was that the repairing method for this configuration could effectively improve the bearing capacity of the original structure, and the adhesive performance was more stable. For SPC structure, debonding of the patch was the primary failure mode with only a 94% strength recovery rate. Besides, the strain concentration of both repairing structures was located in the substrate near the upper and lower edges of the patch. It can be concluded that the repairing technology of SP structure is sufficient to be used in civil aircraft repair, while that of SPC structure needs to be further improved.