Using FGM concept and combined of XFEM-CZM technics to predict the damage in carbon/carbon-epoxy graded composites

Abstract

The study and the proposal of the concepts of reinforcement in the notched structures, present an objective for many researchers. Recently, the use of bi-materials and graduated materials limits the choice to have more graduation concepts, except that the UD (uni-directional) fiber composites limit the choice to have more grading concepts. Through the finite element method and using the ABAQUS computer code, the main objective of this work is to analyze the damage of the graded Carbon/Carbon-Epoxy composite, using the FGM concept. This composite IM7/8552 in two qualities of fibers housed in the same epoxy matrix named CFRP-1 and CFRP-2, is graduated by row of finite elements to the size of fiber diameters according to the thickness. This approximation of the real behavior with more precision in the graduation is carried out by a proposed meshing technique, which gives a combination between XFEM and CZM. The CZM layers are introduced according to the thickness between the rows of finite elements. The graduation is in the volume of fibers between these two qualities, remains constant in the composite at 60%. A volume fraction exponent named (n) gives it. The response and the damage under the effect of different CFRP graduation parameters have been highlighted in this work by force-displacement and crack propagation path curves.