Abstract
For achievement of high strength and light weight of auto body, composite is widely used in automotive components. Especially, the applicability of carbon fiber reinforced plastic (CFRP) as light-weight and high strength material is being considered. However, there are many difficulties to design automotive component by using CFRP because of the strong anisotropy of material according to the fiber orientation and complex fracture modes such as fiber, matrix and delamination failure. The objective of this research is to suggest numerical analysis method for predicting the stiffness and the onset of fracture of automotive components manufactured by carbon composite. CFRP has the various material properties according to the stacking sequence of fibers. We evaluate the modulus, ultimate strength and the information of fracture such as fracture initiation and fracture mode according to the fiber characteristics of the composite manufactured by carbon/epoxy prepreg through the uniaxial tension(ASTM 3039) and compression test(ASTM 3410). In order to simulate the material behavior accurately, the anisotropic material behavior is formulated and fracture criteria based on Tsai-Wu quadratic criterion are applied to the analysis. For the verification of the analysis scheme which applied in this paper, numerical analysis for tensile deformation of the specimen with a hole at the center is carried out and compared with the result of the experiment in the view point of the stiffness, fracture initiation and fracture mode. The load-displacement data and the fracture shapes of the hole-plate specimens will be presented according to the fiber orientation of the composite. The suggested analysis process will show the accuracy for the description of the stress distribution around the hole and fracture which initiates from the hole, comparing to results from the existing analysis method and experiments. As an application, the numerical simulation for lateral load of the cylindrical tube manufactured by filament winding process will be presented.
KEYWORDS – CFRP, Numerical Analysis, Anisotropy, Fracture, Automotive Component