Consolidation mechanism of composite corners cured on convex and concave tools

Abstract

Process monitoring of L-shaped composite laminates is performed using embeddable shape sensors to clarify dynamic ply deformation during consolidation. In this study, three testing conditions are set, depending on whether convex or concave tools are used for layup and curing. Deformation of the composite corner that occurs during all manufacturing of layup, pressurizing, and heating is presented to derive different consolidation mechanisms leading to corner thinning on a convex tool and corner thickening on a concave tool. Curing with the convex tool results in ply sliding and resin outflow, while curing with the concave tool results in ply bridging and resin inflow. Four-point bending test is then conducted to determine the effect of consolidation deformation on the corner strength. Results indicate that tool selection for layup and curing significantly affects the consolidation deformation and quality of the cured part.