Chapter 3 - Preform Consolidation

Abstract

Liquid moulding processes are currently the only viable techniques that can be used to successfully consolidate 30 fiber preforms. There are many different styles of liquid moulding, but they all essentially fall into the main groupings of Resin Transfer Molding (RTM), Resin Film Infusion (RFI), and the Seemann Composite Resin Infusion Process (SCRIMP). The RTM process is characterized by a primarily in-plane flow of the resin through the preform. The resin is driven into the preform by the pressure of a pump. For very thick or complex shaped parts, there is an element of through-thickness resin flow, but essentially the movement of the resin is within the plane of the preform. In the RFI process, the resin film is placed against the prepared tool surface, covering the necessary part surface area, and the preform is placed on top of the film. A release film, to aid in part removal, and a breather material, to enable the generation of vacuum within the bagged area, is then laid on top of the preform. Like the RTM process, SCRIMP introduces liquid resin from an external source into the part via a resin inlet port. However, in a similar fashion to RFI, the primary resin flow direction is through the thickness of the preform.