2019 年 85 巻 869 号 p. 18-00304
An accurate fracture estimation of carbon fiber reinforced plastic (CFRP) is indispensable for adequate design with reliability and economization of high pressure hydrogen tank made by filament winding (FW) method for automobile. Authors have approached to the burst pressure estimation problems of the tank substituted by cross shape specimen representing fiber bundle situation in CFRP layer of the tank. The specimen is manufactured by filament winding machine to form crimps of fiber bundles crossover by right angle. Its mesoscopic structure of fiber bundle and matrix resin is precisely modeled for the finite element analysis. Highly non-linear material model of resin strength has been developed to predict breakage load and elongation of the specimen under biaxial tensile test. We have elucidated strain-rate dependency and tension-compression asymmetry in resin strength, and transverse strength of fiber bundle govern the fracture process of the specimen. Other types of specimens, such as unidirectional, crossover by 45 degrees with crimps and layered by right angle, are employed to demonstrate the validity of the proposed methodology.
