Effects of resin distribution patterns on through-thickness air removal in vacuum-bag-only prepregs. (March 2020)

• Record Type: Journal Article
• Authors: Schechter, Sarah G.K.; Centea, Timotei; Nutt, Steven
• Is Part Of: Composites. Volume 130(2020)
• Publication Date: 2020-03
• Subjects: A. Prepreg -- A. Polymer-matrix composites -- B. Permeability -- E. Out of autoclave processing; Composite materials -- Periodicals; Manufacturing processes -- Periodicals; Composite materials; Manufacturing processes; Periodicals; 620.11805
• DOI: 10.1016/j.compositesa.2019.105723
• Languages: English
• ISSNs: 1359-835X

Abstract

Abstract: Prepregs with discontinuous resin patterns facilitate air removal and impart robustness to vacuum-bag-only processing of composites. However, optimal pattern characteristics have not yet been identified. A geometric model was developed to guide the fabrication of prepregs with various discontinuous patterns and laminates with different orientations and ply counts. The model was used to evaluate metrics related to gas transport: projected surface area exposed, sealed interfaces, and tortuosity. Statistical analysis revealed that single layer surface area exposed and ply count had the greatest effect on projected surface area exposed; orientation had the greatest effect on sealed interfaces and tortuosity. From these insights, prototype prepregs were fabricated to measure through-thickness permeability. Prepregs with a large percentage of sealed interfaces and high tortuosity exhibited lower permeability. The study demonstrated a methodology to differentiate/screen patterns for gas transport efficiency. The model can guide prepreg design and support robust production of composites via out-of-autoclave manufacturing.