Experimental Investigation on Performance Evaluation of Composite T-Stiffened Skins Fabricated by Integral Molding Technologies Under Tensile Loading

Composite T-stiffened skins widely used in aircraft industry nowadays were fabricated by using the co-curing, co-bonding and secondary bonding processes. The stiffener thickness and the tensile property of T-stiffened skins under tensile loading were performed as evaluation indexes to evaluate the manufacturing quality and mechanical property of T-stiffened skins, respectively. The results show that the better manufacturing quality and higher tensile property of T-stiffened skins are found in the co-bonding process, and the tensile property increases with the increase of the adhesive film thickness in the co-bonding process. The co-curing process provides a similar tensile property of the co-bonding process with 0.15 mm thickness adhesive film, but different failure modes in the stiffener/skin interface are found in co-curing and co-bonding processes. Moreover, the filler content and the filler type in the triangle filling area of T-stiffened skins also have significant influence on the tensile property of T-stiffened skins, and rolling adhesive films as fillers into the triangle filling area exhibits the highest tensile property in five kinds of fillers during the co-bonding process.