Experimental investigation of transverse permeability applied to liquid molding

• Published in: Polymer composites Vol. 40; no. 10; pp. 3938 - 3946
• Main Authors: Trindade, Rafael Scheer, Ribeiro, Affonso Calsing, Souza, Jeferson Avila, Amico, Sandro Campos
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01-10-2019; Blackwell Publishing Ltd
• Subjects: Fiber volume fraction; Flow velocity; Permeability; Photomicrographs; Polymers; Working fluids
• ISSN: 0272-8397; 1548-0569
• DOI: 10.1002/pc.25254

The study of transverse permeability of fibrous reinforcements has become increasingly important when liquid‐molding processes started being more widely employed to obtain more complex‐shaped or thick parts. In this paper, a system has been specially built to measure transverse permeability of fabrics with different characteristics based on the correlation between pressure difference and flow rate. Influence of preform thickness and working fluid on permeability was initially evaluated to validate the measurements. Next, the effect of fiber type and fiber volume fraction on permeability was investigated. In‐plane permeability of the reinforcements was also measured to study the relative importance between in‐plane and transverse permeabilities within a fiber content range, which varied differently for the various reinforcements. The results were discussed with the aid of fiber compaction experiments and micrographs. POLYM. COMPOS., 40:3938–3946, 2019. © 2019 Society of Plastics Engineers