Flow Instabilities during the Squeeze Flow of Multiaxial Laminates

Abstract

This paper examines the effect that ply arrangement has on the processing characteristics of aligned long fiber reinforced composite laminates. More specifically, this study focuses on the difference between the consolidation squeeze flow behavior of unidirectional and multiaxial ply laminates. A commercially produced material tape composed of aligned carbon fibers in a thermoplastic PEEK matrix (APC-2) was used to construct the laminates. Using specially designed hot platens, constant platen closure rate squeeze flow-experiments were performed on 70 ply unidirectional [0°] laminates. Flow visualization techniques were then used to measure the velocity profile of the material during flow. Similar squeeze flow experiments were also carried out on macro-ply [0₁₄,90₁₄,0₇] _s and cross-ply [0°,90°]_18s laminates. Comparisons are made between the generated squeeze forces and macroscopic flow deformation of the three laminate configurations.