Influence of core fillers on resin flow and fiber compaction of cocured skin‐to‐stiffener structures

Abstract The integral molding technology is the development of composite structures. In this study, an experimental integral technology of cocuring was applied to fabricate T‐stiffened skins. A study was undertaken to determine the effect of fillers in stiffener core on resin flow and fiber compaction of T‐stiffened skins. A new application of transferring pressure film was carried out to measure the pressure distribution in T‐stiffeners. The characteristics of resin flow were investigated by the bleeding quantity and the stiffener thickness in prebleeding process. The experimental results indicated that nonuniform pressure obviously distributed in T‐stiffeners, especially the lowest pressure exhibited in stiffener corner. Resin‐rich defect and highest thickness were frequently obtained in stiffener corner. However, rolling unidirectional prepregs as fillers into the stiffener core of T‐stiffened skins caused an increase of pressure in stiffener corner, gave the stiffener corner to the opportunity to remove the resin‐rich defect by hindering resin flow into the stiffener corner, and consequently contributed to a significant increase in the fiber compaction and manufacturing quality of T‐stiffeners. POLYM. COMPOS., 31:1360–1368, 2010. © 2009 Society of Plastics Engineers