Generalized Stress Intensity Factor at the Corner of Debonded Fiber Ends
Nao-Aki NODA, Yuki NAGAO, Satoshi IIMA and Yasushi TAKASE
Abstract:This paper deals with intensity of singular stress field at the corner of debonded ends of an elastic cylindrical inclusion in an infinite body under tension. The problem is formulated as a system of singular integral equations, where unknown functions are densities of body forces distributed in infinite bodies having the same elastic constants as those of matrix and inclusion. In the numerical analysis, the unknown function of the body force densities are expressed as a linear combination of two types of fundamental density function and power series, where the fundamental density functions are chosen to express the symmetric stress singularity of the from γλ1-1 and the skew-symmetrics stress singularity of the from γλ1-1. Then, generalized stress intensity factors, which control the singular stress fields at the end of the cylindrical inclusion are discussed with varying the fiber lengths and elastic modulus ratio. The effect of debonding length on the generalized stress intensity factors is also discussed in comparison with the results of a cylindrical cavity. The results are also compared with ones for a rectangular inclusion. Key Words: Composite material, Fracture mechanics, Fiber, Debonding, Body force method, Stress intensity factor, Singular integral equation, Cylindrical inclusions