FAILURE OF TRANSVERSELY STITCHED RTM LAP JOINTS

An experimental evaluation has been undertaken to investigate the effe ct of transverse stitching on the strength of composite single-lap joi nts. Balanced single-lap joints were considered and the lay-up for the adherends was (0/+/-45/90)(s). Specimens were stitched with Kevlar(TM ) thread in a zigzag pattern and were manufactured by using the resin- transfer moulding (RTM) technique. Experimental results indicated that stitched joints were over 20% stronger than their unstitched counterp arts, The scanning electron microscopy study of the fracture surfaces indicated that the failure is mainly dominated by peel and the stitch threads break inside the adherends and then pull out. (C) 1998 Elsevie r Science Ltd. All rights reserved.