Experimental Evaluation of the Damage Growth Restraining in 90° Layer of Thin-ply CFRP Cross-ply Laminates

Abstract

In this study, a systematic detailed experimental observation was made on the damage growth behavior in 90° layer of cross-ply CFRP laminates. It is generally known that the crack initiation strain is increased with decreasing the thickness of 90° layer. However the mechanism has not been well clarified in the case of very thin thickness such as less than 0.100 mm. We used a thin-ply prepreg developed by SAKAI OVEX CO., LTD with the theoretical minimum thickness of 0.040 mm. As a result of observation, the mode and the growth behavior of the damage were different depending on the ply thickness of 90° layer. It is shown that the damage growth is faster with the 90° layer to be thicker and vice versa. It is suggested that the damage growth behavior can be controlled with the ply thickness of 90° layer based on energy release rates by the FEM simulation.