Interfacial Stresses in Viscoelastic Thin Layer due to Moisture Absorption

Abstract

This paper deals with the stress singularity induced at the interface corner between the viscoelastic thin film and the elastic substrate as the film absorbs moisture from the ambient environment. The thin film is assumed to be a linear viscoelastic material and moisture effects are assumed to be analogous to thermal effects. The time-domain boundary element method is employed to investigate the behavior of interface stresses. The order of the singularity is obtained numerically for a given viscoelastic model. The numerical results exhibit the relaxation of interface stresses and large stress gradients are observed in the vicinity of the free surface. It is shown that the stress singularity factor is relaxed with time, while the order of the singularity increases with time for the viscoelastic model considered.

Analytical elasto-creep model of interfacial thermal stresses and strains in trilayer assemblies

“…the number of assigned divisions (n) could not be made large enough to capture the steepening shear stress gradient at the free ends required to meet the zero shear stress boundary condition. A similar situation was observed by Lee and Kim (2004) in the viscoelastic analysis of interfacial stresses between a viscoelastic thin film and an elastic substrate.…”