Influence of Tool Assembly Schemes and Integral Molding Technologies on Compaction of T-stiffened Skins in Autoclave Process

Abstract

The structure of T-stiffened skins molded integrally by co-curing or co-bonding is widely used in aircraft industry nowadays. Ongoing research focuses on the study of the compaction of simple structure composite components and the analysis of mechanical properties of T-stiffened skins. In this article, using carbon fiber/bismaleimide prepregs, T-stiffened skins were integrally fabricated by different tool assembly schemes in autoclave. The influence of tool assembly schemes and integral molding technologies on the compaction of T-stiffened skins was discussed in detail. A method of self-designing solid pressure testing was introduced to measure the pressure distribution upon T-stiffeners during cure process. The compaction of T-stiffeners was studied quantitatively by thickness distribution and analyzed qualitatively by pressure transferring. The experimental results showed that the pressure distribution in T-stiffeners was significantly influenced by tool assembly schemes and tool radii, which directly affected the compaction of T-stiffeners. The optimum assembly of rigid tool and triangle flexible tool with appropriate stiffness was adopted. In comparisons of co-curing and co-bonding, little difference of compaction in web and flange of T-stiffeners were found except higher thickness in corner section for co-curing.

Keywords

composite co-curing co-bonding stiffener autoclave compaction.

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