Air evacuation during vacuum bag only prepreg processing of honeycomb sandwich structures: In-plane air extraction prior to cure. (January 2015)

• Record Type: Journal Article
• Authors: Levy, Arthur; Kratz, James; Hubert, Pascal
• Is Part Of: Composites. Volume 68(2015)
• Page Start: 365
• Page End: 376
• Publication Date: 2015-01
• Subjects: A. Honeycomb -- C. Analytical modelling -- E. Prepreg -- E. Consolidation; Composite materials -- Periodicals; Manufacturing processes -- Periodicals; Composite materials; Manufacturing processes; Periodicals; 620.11805
• DOI: 10.1016/j.compositesa.2014.10.013
• Languages: English
• ISSNs: 1359-835X

Abstract

Abstract: Out-of-autoclave (OoA) prepregs offer good in-plane air permeability that enable efficient in-plane air-extraction. In this paper, OoA prepregs skins were applied to honeycomb sandwich structures, to act as in-plane air extraction media during the vacuum hold prior to cure. An in-plane extraction model was developed to predict the pressure drop in a honeycomb sandwich structure. The model was experimentally validated by measuring the local pressure in a 1 m long sandwich structure. The model provides design guidelines vacuum hold duration to achieve a given final pressure in the part prior to cure. Finally, the in-plane and transverse extraction strategies were compared for large parts. The in-plane extraction was faster for parts smaller than 0.4 m .