Materials Characterisation and Analysis for Flow Simulation of Liquid Resin Infusion

• Published in: Applied composite materials 2015-06, Vol.22 (3), p.323-341
• Main Authors: Sirtautas, J., Pickett, A. K., George, A.
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Industrial Chemistry/Chemical Engineering; Materials Science; Polymer Sciences
• ISSN: 0929-189X; 1573-4897
• DOI: 10.1007/s10443-014-9411-6

Liquid Resin Infusion (LRI) processes including VARI and VARTM have received increasing attention in recent years, particularly for infusion of large parts, or for low volume production. This method avoids the need for costly matched metal tooling as used in Resin Transfer Moulding (RTM) and can provide fast infusion if used in combination with flow media. Full material characterisation for LRI analysis requires models for three dimensional fabric permeability as a function of fibre volume content, fabric through-thickness compliance as a function of resin pressure, flow media permeability and resin viscosity. The characterisation of fabric relaxation during infusion is usually determined from cyclic compaction tests on saturated fabrics. This work presents an alternative method to determine the compressibility by using LRI flow simulation and fitting a model to experimental thickness measurements during LRI. The flow media is usually assumed to have isotropic permeability, but this work shows greater simulation accuracy from combining the flow media with separation plies as a combined orthotropic material. The permeability of this combined media can also be determined by fitting the model with simulation to LRI flow measurements. The constitutive models and the finite element solution were validated by simulation of the infusion of a complex aerospace demonstrator part.