Title: VACUUM INDUCED PREFORM RELAXATION FOR THE MANUFACTURING OF THERMOSET COMPOSITES WITH IMPERMEABLE INTERLAYERS

Authors: Tania Lavaggi, Sagar Doshi, Dean Vanegas, Kushal Mehta, John W. Gillespie Jr., Suresh G. Advani

DOI: 10.33599/nasampe/s.23.0192

Abstract: Composites used in impact applications are often susceptible to delaminations when subjected to high-energy impact events and could result in loss of residual stiffness and strength. To improve the delamination resistance, researchers have used tough thermoplastic interlayers. However, the inclusion of the impermeable layers in the fabric stacking sequence adds difficulties to resin infusion processes, such as, preventing the resin from flowing through the thickness of the preform and reducing the in-plane permeability of the system. In the case of vacuum assisted resin transfer molding (VARTM), inducing relaxation on the preform may help to mitigate the effects of the interlayers. In this work, the flow of a thermoset polymer in composites formed by sub-laminates of glass fabrics separated by impermeable interlayers is monitored while performing VARTM experiments. A vacuum chamber is placed on top of the vacuum bag to induce relaxation in the preform during the injection of the polymer. When relaxation is induced, the permeability of the system increases substantially. The presented methodology may eventually allow the manufacturing of thick-section composite parts with thermoplastic interlayers with increased damage tolerance. In addition to demonstrating proof-of-concept, this work aims to identify potential challenges associated with the process.

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Conference: SAMPE 2023

Publication Date: 2023/04/17

SKU: TP23-0000000192

Pages: 14

Price: $28.00