Abstract
In this study, we made a systematic detailed experimental observation 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 thinner 90° layer. However the mechanism has not been well clarified. We used a thin-ply prepreg developed by Sakai Ovex Co., Ltd with the theoretical minimum thickness of 40 μm. As a result of observation, the damage mode and the damage growth behavior are different depending on the ply thickness of 90°layer. It is shown that the damage growth is faster with thicker 90°layer (Mode A), while it is shower with thicker 90°layer (Mode B). In addition, It is observed that the crack opening displacement (COD) is larger in Mode A and smaller in Mode B. It is suggested that the damage growth behavior can be controlled with the ply thickness of 90°layer to explain the superiority of thin-ply CFRP laminates.
