Axisymmetric partial slip contact of a functionally graded piezoelectric coating under a conducting punch

This article considered the axisymmetric partial slip contact problem of a functionally graded piezoelectric coated half-space indented by a rigid spherical punch subjected to a normal load. It is assumed that the punch within the contact region is a perfect conductor with a constant electric potential. The electro-mechanical properties of the functionally graded piezoelectric materials vary exponentially along the thickness direction. The whole contact region consists of an inner circular stick region surrounded by an outer annular slip region obeying Coulomb’s law of friction. The problem is reduced to a set of coupled Cauchy singular integral equations by employing the Hankel integral transform. An iterative method is used to determine the unknown stick/slip region, normal contact pressure, electric charge, and radial tangential traction. The effects of the resultant electric charge, friction coefficient, and gradient index on the surface electro-mechanical fields are presented in detail.