Drop weight impact studies on rib-knit RTM laminates

Six types of weft rib knit preforms developed on a flat bed hand knitting machine from E-glass rovings of 300 Tex have been used in this study. RTM laminates prepared from these six preforms were drop weight tested using a Dynatup GRC model with 830-I data acquisition software. Glass/epoxy woven fabric composites with varied lay-up sequences were used for comparison and evaluation with these knit laminates under identifical test conditions. Laminates from knits with added reinforcements in the course direction have clearly exhibited characteristics failure modes and superior energy absorbing capabilities as compared to the corresponding woven counterparts.