Quantitative Evaluation for Effect of Moisture on Fracture of 2DPGFRP by AE Method

Abstract

The addition of particulate flame retardant to matrix resin is necessary when GFRP with no flammability is applied to the field needed that property. However, that method accompany the increase in resin viscosity. The increase in resin viscosity affects the formability of GFRP and it cause the decline of mechanical properties. Therefore, we focused on GFRP that has the two diameter particles added (2DPGFRP) for the compatibility of the suppression of increased viscosity and the grant of non-flammability. In our past study, the 2DPGFRP was showed to have unique mechanical properties that the difference in bending strength depending on which the resin applied surface (Top side) and the mold surface (Bottom surface) is tensile side. In addition, the origin of fracture on 2DPGFRP is confirmed with the interface of particle/resin instead of the interface of fiber/resin which is the origin of fracture on general GFRP. Furthermore, the origin of fracture was changed from the interface of particle/resin to interface of fiber/resin due to containing moisture into the specimen, and the decline of bending strength by that phenomenon. The quantitative evaluation about this phenomenon is an important issue for the practical application of 2DPGFRP. However, the quantitative reports about that are few. Therefore, in this research, the quantitative evaluation for the effect of moisture for the fracture behavior of 2DPGFRP using the data obtained by AE measurement was conducted.