Evolution of the damage onset and morphology in [0/90n/0] laminates when increasing the ply thickness

In a previous paper, París et al [1], the authors proposed physically based explanation (without employing fitting parameters) of scale effect in composites, which gave new insight on in-situ strength concept. The was identification mechanisms damage involved “failure” layer, application Linear Elastic Fracture Mechanics to these mechanisms, predictions obtained from models reproducing and some experimental observations. It could be immediately deduced that concept much more complicated than simply associated with failure lamina, since what understood as fact may involve variety patterns that, accordance given size effect, extremely dependent thickness layer affected. This lead significant alteration performance laminate function layer. value laminas laminate, has been limited due technological reasons manufacturing laminas, presents now wide range values, starting ultra-thin plies (20 µm thickness). is obvious point view increase produces reduction cost being an direct temptation for composite structures manufacturers. purpose present paper first all carry out extensive investigation clarify different damages appear most exposed when increasing which, itself, will afford determinant information about use thick laminate. Additionally, it allow establish correlation between explanations observations 90 degrees