Estimation of singular stress field of an interface crack in orthotropic dissimilar material by using the solution for isotropic dissimilar material

Abstract

For isotropic dissimilar materials, it is well known that the stress state can be expressed by two independent material composite parameters named Dundurs parameters αiso, βiso. Similar composite parameters were also derived for orthotropic dissimilar materials as α , β , ΓA , ΓB , ρA , ρB . Compared to two parameters in isotropic dissimilar materials, anisotropic dissimilar materials have such six independent material parameters, making it much more difficult to use previous analysis results and requiring the new analysis each time. In this study, first, the interface crack in orthotropic dissimilar materials is analyzed by applying the proportional method. Second, the singular stress field in orthotropic materials is compared with that in the isotropic dissimilar material under the condition α = αiso，β = βiso. The results show that the singular stress field in orthotropic dissimilar material can be evaluated within a few percent error in most cases from that in isotropic dissimilar material when α = αiso，β = βiso. In this isotropic replacement by applying α = αiso，β = βiso, the singular interface stress distributions in orthotropic dissimilar plates can be estimated within the 10% error even when the material anisotropy is widely changed.

Keywords

• fracture mechanics
• stress intensity factor
• interface crack
• orthotropic dissimilar materials
• material composite parameters
• dundurs parameters