Influence of Pre-consolidation parameters on the preforming deformation mechanisms of polymeric composites

Abstract

The manufacture of composite structures with prepreg materials is typically performed over the desired shape using different methods, such as double diaphragm process. The double diaphragm forming process requires preheating and compaction pressure, which causes some degree of consolidation within the composite sheets. This initial step, pre-consolidation, has an effect on the deformation mechanisms, including in-plane and out-of-plane properties, that controls the material’s formability. This paper aims to investigate the effect of pre-consolidation parameters, specifically: processing temperature and compaction pressure, on the in-plane deformation mechanisms. The research is mainly focused on the deformation mechanisms of 8-harness satin (8HS) weave carbon/epoxy prepreg under in-plane shearing using picture frame test. The results of the study demonstrate that an increase in pre-consolidation temperature and pressure, consequences in decreased in-plane shear deformability of woven textile prepreg. However, optimum pre-consolidation parameters must be attained to enhance resin flow within fiber tows and to avert micro-voids.