Evaluation and analysis of interlaminar fracture toughness of bead filled matrix hybrid composite materials using orthotropic fracture mechanics

Evaluation of Mode I interlaminar fracture toughness for unidirectional hybrid composites fabricated with a bead filled epoxies was carried out. The two important fracture toughness parameters, G_IC and K_IC values of hybrid composites, were reviewed in accordance with the orthotropic fracture model. The deviation of measured G_IC and K_IC values from predicted values were explained based on the critical review of the basic assumption of orthotropic fracture model and characteristic material properties of hybrid composites. It can be said that, basically, the orthotropic fracture model can be used for evaluation of hybrid composite materials. However, careful analysis for G_IC and K_IC values which were derived from different source and some correction factor for K_IC values are necessary.