A two‐dimensional theoretical approach is developed to describe the thermal and elastic fields in the vicinity of a line thermal source located at the junction between two bonded materials. A modified system of thermoelastic equations is obtained and solutions are found. The temperature distributions give evidence for a depth‐dependent transverse thermal flow. From the shape of the mechanical deformations at the interface, the ability of different pairs of materials to be applied as thermoacoustic transducers is qualitatively deduced.