A parametric flow visualisation study on the impregnation and consolidation stages of the Wet Compression Moulding process. Part I: Process parameters

The Wet Compression Moulding (WCM) process is a recently re-introduced production technique increasingly adopted in industry, most commonly in the automotive sector, for high volume production of structural reinforced plastics components. To date, process design parameters have been established through experiences gained by technologists. To develop an understanding of the influence of process and material parameters, two flow visualisation facilities have been developed to investigate the resin application, consolidation, and postfilling stages of WCM. This article presents a study on process parameters, including hold time, resin mass, edge clamping, and press profile. All studied parameters have been shown to influence the magnitude of resin pressure reached at the completion of the consolidation, as well as the required tool clamping forces. The mode of press control is also shown to affect the rate of pressure decay during post-filling, providing a mechanism for reducing void diameter at the onset of resin gelation.