Analysis of a curved interfacial crack between viscoelastic foam and anisotropic composites under antiplane shear

The analysis of curved interfacial crack between viscoelastic foam and anisotropic composites was conducted under antiplane shear loading applied at infinity. In the analysis, in order to represent viscoelastic behavior of foam, the Kelvin-Maxwell model was incorporated and Laplace transform was applied to treat the viscoelastic characteristics of foam. The curved interfacial crack problem was reduced to a Hilbert problem and a closed-form asymptotic solution was derived. The stress intensity factors in the vicinity of the interfacial crack tip were predicted by considering both anisotropic characteristics of composites and viscoelastic properties of foam. It was found from the analysis that the stress intensity factor was governed by material properties such as shear modulus and relaxation time, and increased with the increase in the curvature as well as the ratio of stiffness coefficients of composite materials. It was also observed that the effect of fiber orientation in the composite materials on the stress intensity factor decreased with the increase in the difference in stiffness coefficients between foam and composite.