Characterization of Textile Draping Behaviours for Composite Manufacturing Processes

Abstract

The manufacture of composite components can be achieved using multiple processes. Once such process is the vacuum assisted resin transfer moulding method for manufacturing composite components. This process involves draping a fabric reinforcement over a mould, and then infusing the fabric reinforcement with resin under vacuum. The weight of the atmosphere pushes down on the fabric while the resin is curing, which increases the fibre volume fraction in the final part. The process is widely used in manufacturing composite components for aerospace applications, because it allows the manufacture of large and often complex parts. It also reduces tooling costs when compared to other composite manufacturing methods. The process of draping the fabric onto the mould is of significant interest. Draping fabrics onto moulds forces them to deform into the shape of the mould, creating several difficulties related to fabric bending, fabric in-plane shearing, friction between layers of fabric, and spring back of fabrics once draped. Several testing methods are adapted from literature; others are created in this work in order to characterize the mechanical behaviour of fabrics. The mechanical parameters characterized through testing enable calculations of terms of draping energy. The energy required for draping a mould is associated with the difficulty of draping the fabric onto that mould. Drape energy calculations allow for direct comparisons of the draping performance of different fabrics and draping strategies.