Relationship between Fractal Dimensions of AE Amplitude Distribution and Fracture Patterns of Fatigue-Loaded FRPP
Sotoaki KIDA, Akihito SERIZAWA, Noriyuki TAKANO, Megumu SUZUKI, Takeshi MORIWAKI and Toshiharu SAKAGUCHI
Abstract:The tensile test was conducted on the fatigue-damaged FRPP specimens, inclusing fiber content in weight of 50% made by direct injection molding method. Fracture patterns were examined by the fractal dimensions from the AE amplitude distributions detected during the fracture process and the strain energy stored to fracture. The fracture patterns of FRPP specimens are mainly dominant at the fiber debonding from the AE frequency analysis obtained during the tensile test. The relationship between the normalized fractal dimensions of FRPP and the ratio of cyclic numbers N/Nf shows the upper convex . It resembles the relationship between the standardized energy release rate at the fiber debonding and the fiber debonding angle in model composite specimen. The fracture patterns are also found on the relationship between the strain energy and N/Nf. These results are compared with those of the fatigue-damaged FRPA specimens. Key Words:Acoustic Emission, Reinforced Plastics, Fatigue, Fractal, Fracture Pattern, Amplitude Distribution