Imperfect Interface Conditions Research Articles

Extremum principles for elastic heterogenous media with imperfect interfaces and their application to bounding of effective moduli

T he E lasticity extremum principles of minimum potential and minimum complementary energies are extended to the case of heterogenous media with imperfect interface conditions. The extended principles are applied to construct bounds for the effective elastic moduli of two-phase materials and polycrystalline aggregates with imperfect interfaces.

The Spherical Inclusion With Imperfect Interface

A rigorous solution of the spherical inclusion problem with remote uniform strain or stress and imperfect elastic spring-type interface conditions is presented. In the case of thin elastic interphase, the interface spring constants are expressed in terms of interphase elastic properties and thickness. The state of strain/stress in the inclusion is nonhomogeneous for imperfect interface conditions in contrast to the homogeneous state for perfect interface condition. Numerical results are given to demonstrate the significance of imperfect interface effects.

Thermoelastic properties of fiber composites with imperfect interface

Imperfect interface conditions are defined in terms of linear relations between interface tractions and displacement jumps. All of the thermoelastic properties of unidirectional fiber composites with such interface conditions are evaluated on the basis of the generalized self consistent scheme (GSCS) model. Results for elastic interphase are obtained as a special case by evaluation of interface parameters in terms of interphase characteristics. Numerical evaluation has shown that imperfect interface may have a significant effect on transverse thermal expansion coefficient, transverse shear and Young's moduli and axial shear modulus, a moderate effect on axial Poisson's ratio, small effect on axial thermal expansion coefficient and an insignificant effect on axial Young's modulus.