Study on the coated isotropic thermoelastic material based on the three-dimensional Green’s function for a point heat source

• 3D Green׳s function of coated isotropic thermoelastic material is presented.
• The role of coating layer in redistributing stresses is investigated.
• The tensile and shear debonding is easy to happen near the heat source.

Three-dimensional Green׳s function for a point heat source acting on the surface of a coated isotropic thermoelastic material is investigated in this paper to improve our understanding about the interface mechanisms of coating/substrate system. Based on the general solution of isotropic thermoelastic materials expressed by harmonic functions, the corresponding harmonic functions with undetermined constants for coating layer and semi-infinite substrate are constructed by the trial-and-error method, respectively. The thermoelastic field can be obtained by substituting the harmonic functions into the general solution. The constants can be determined by the boundary conditions of the surface and the continuous conditions of the interface between the coating layer with the semi-infinite substrate. Numerical results are exhibited in form of contours and some valuable conclusions for interface effect, interface debonding and stress field distortion are presented.