Reducing the void content and its variability in polymeric fibre reinforced composite test specimens using a vacuum injection moulding process

To obtain acceptable accuracy and consistency in the mechanical testing of polymeric fibre reinforced composities, it is important that both the fibre alignment and the void content be precisely controlled. In particular, a high void content can greatly affect both the variability and the value of the mechanical strengths of the composite. This paper describes the use of a simple vacuum injection moulding process to produce fibre reinforced composites that have a consistently low void content, of about 1·3%, and a correspondingly high and consistent flexural strength.