Title: A Validation Study for Modeling Strategies Designed to Predict Cure Defects Including Porosity and Wrinkling During Composite Processing

Authors: Curtis W. Hickmott, Paulo Silva, Alireza Forghani, Frank L. Palmieri, Brian W. Grimsley, Brian R. Coxon, Goran Fernlund, Anoush Poursartip

DOI: 10.33599/nasampe/s.21.0602

Abstract: The performance of composite structures is highly dependent on the manufacturing processes and the resulting part quality. Cure defects such as porosity and wrinkling are common challenges in manufacturing due to the strict requirements surrounding composite parts and the complexity of the defect formation. The primary sources of porosity include bag leaks, entrapped air in the system, off gassing of volatiles, and cure shrinkage. Mechanisms which can mitigate porosity include removal of air from the system and sufficient resin pressure to keep volatiles in solution. The primary sources of wrinkling are the build-up of excess carbon fiber length due to debulking and consolidation; however, wrinkling is inhibited by the ability of plies to shear or slide past one another. Under the NASA Advanced Composites Project (ACP), a physics-based modeling approach has been developed for modeling the formation of porosity and wrinkling as a function of these mechanisms. In this work, the modeling strategies and their implementation were investigated on a series of validation cases, and then compared to experimental data.

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Conference: SAMPE NEXUS 2021

Publication Date: 2021/06/29

SKU: TP21-0000000602

Pages: 13

Price: FREE