Evaluation of transverse Young's modulus of unidirectional carbon fiber reinforced plastics

Abstract

The transverse Young's modulus of unidirectional carbon fiber reinforced plastics(CFRP) was measured by three points bending tests and compared with values calculated using finite element method(FEM). To calculate the transverse Young's modulus, we developed a 3-dimensional finite element method program by modifying the hexagonal array model in consideration of the anisotropy of carbon fiber and the effect of interface between carbon fiber and matrix. The values calculated without consideration of the effect of interface were smaller than the experimental data. The FEM analysis indicated that the transverse Young's modulus of CFRP was changed largely with the change of the Young's modulus of the interface layer when the modulus of the interface was less than that of the matrix.