RESIN INFUSION MANUFACTURING OF PRIMARY STRUCTURES WITH CORE

摘要

Pressurized fuselage structures made with cored laminates are becoming more common incomposite airplane designs. Using a cored laminate allows reduction in the amount of internalstiffening members as the fuselage skin supplies much of the stiffness. Cytec EngineeredMaterials (CEM) initiated an effort to develop and demonstrate a new method for fabricatingthese types of structures. In the past, these structures have been manufactured with traditionalpre-preg materials and layup methods (hand and automated layup) and cured using an autoclave.Out-of-autoclave (OOA) prepreg materials and oven cure have also been used with varyingdegrees of success. To date, this type of structure has not been fabricated using a vacuumassistedresin transfer molding (VaRTM) process. VaRTM offers advantages over traditionalprepreg layup techniques in that the dry textile is highly conformable and allows the process tobe completed out of the autoclave. This provides the benefits of reduced darts and butt splices inthe layup resulting in improved laminate quality, improved lay down rate and lowermanufacturing cost.The most geometrically complex sections of a fuselage are the fore and aft sections. Thesesections have double curvature geometry. To demonstrate the use of VaRTM on cored laminates,CEM's Applications Engineering and Research group (AE&R) selected a starboard “half”section. The part was fabricated in a two step approach that allowed for in-house trimming ofcore details, elimination of core crush and a reduction in seams and overlaps due to improveddrape.