The effect of interface imperfection and external loading on the axisymmetric contact with a coated solid

A method is proposed to solve a contact problem for an elastic punch and elastic layer bonded to an elastic half-space. The boundary conditions at the interface model the imperfect adhesion between the layer and substrate. The effect of additional loading applied to the layer outside the contact region is taken into account. The solution of the axisymmetric contact problem is obtained by using Hankel transform and iteration methods. The stresses within the coated body which is in contact with the spherical punch or with the punch having a flat base and rounded edges are calculated. The analysis of the dependence of the contact characteristics and stresses inside the coated body on the geometrical and mechanical properties of the layer and the substrate, parameter characterising the imperfect adhesion, punch shape, and an additional load is presented.