A solution to the thermo-elastic interface crack branching in dissimilar anisotropic bi-material media

Abstract

An interface crack or delamination may often branch out of the interface in a laminated composite due to thermal stresses developing around the delamination/crack tip when the media is exposed to heat flow induced by environmental events such as a sudden short-duration fire. In this paper, the thermo-elastic problem of interface crack branching in dissimilar anisotropic bi-media is studied by using the theory of StrohÕs dislocation formalism, extended to thermo-elasticity in matrix notation. Based on the complex variable method and the analytical continuation principle, the thermo-elastic interface crack/delamination problem is examined and a general solution in compact form is derived for dissimilar anisotropic bi-media. A set of GreenÕs functions is proposed for the dislocations (conventional dislocation and thermal dislocation/heat vortex) in anisotropic bi-media. These functions may be more suitable than those which have appeared in the literature on addressing thermo-elastic interface crack branching in dissimilar anisotropic bi-materials. Using the contour integral method, a closed form solution to the interaction between the dislocations and the interface crack is obtained. Within the scope of linear fracture mechanics, the thermo-elastic problem of interface crack branching is then solved by modelling the branched portion as a continuous distribution of dislocations. The influence of thermal loading and thermal properties on the branching behavior is examined, and criteria for predicting interface crack branching are suggested, based on the extensive numerical results from the study of various cases.

Experiment Research on Initiation and Micro-propagation of the Interface Crack in the Hard Cladding Material 5Cr2Ni08C/Q235

“…Hu Tuo [4] used finite element numerical simulation method to study the mechanism of the interface crack propagation in the composite materials, the result showed that the interface crack in the composite pressure vessel appeared elliptical propagation and propagated to the material with small elastic modulus. R. Li et al [5] researched the influence of the thermal load on the interface crack branched propagation in anisotropic elastic material using numerical simulation method. Yu Hanghai et al [6] studied the resistance force of crack propagation in BNNT/Si 3 N 4 composites with the finite element method.…”