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A component (10) having a thermal barrier coating (14) exhibiting an improved resistance to thermal shock. A plurality of stress relieving cracks (22) are formed at the free surface (24) of the thermal barrier coating as a result of the expansion of an inclusion (20) having a higher coefficient of t

A component (10) having a thermal barrier coating (14) exhibiting an improved resistance to thermal shock. A plurality of stress relieving cracks (22) are formed at the free surface (24) of the thermal barrier coating as a result of the expansion of an inclusion (20) having a higher coefficient of thermal expansion than that of the surrounding matrix material (16). The inclusions function as crack initiators during the fabrication process as well as crack arrestors preventing the propagation of the cracks farther into the matrix material. The inclusion material may be selected to have an evaporation temperature that is less than the peak matrix material processing temperature, wherein the inclusion material will evaporate to leave a plurality of voids (30). In one embodiment, a superalloy substrate (12) is coated with a ceramic thermal barrier coating material having a plurality of spherical polymer inclusions disposed below its free surface. When the ceramic material is heated to its sintering temperature, the polymer inclusions induce cracks in the ceramic material through which the polymer then diffuses upon its subsequent evaporation.

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1. A component adapted for operation at an elevated temperature, the component comprising:a substrate material; a thermal barrier coating disposed on the substrate material, the thermal barrier coating further comprising: a layer of ceramic material; a plurality of inclusions having a coefficient of

1. A component adapted for operation at an elevated temperature, the component comprising:a substrate material; a thermal barrier coating disposed on the substrate material, the thermal barrier coating further comprising: a layer of ceramic material; a plurality of inclusions having a coefficient of thermal expansion greater than that of the ceramic material disposed below a free surface of the ceramic material; and a crack extending from respective ones of the plurality of the inclusions to the free surface of the ceramic material. 2. The component of claim 1, further comprising:the substrate material comprises a superalloy material; the ceramic material comprises one of the group of alumina, zirconia, yttria-stabilized zirconia, and magnesia-stabilized zirconia; and wherein the inclusions comprise a material having a coefficient of thermal expansion greater than that of the ceramic material and comprise one of the group of a polymer, ceramic, glass and metal material. 3. The component of claim 1, wherein the inclusions comprise hollow spheres of material having a coefficient of thermal expansion greater than that of the ceramic material.4. The component of claim 1, wherein the inclusions comprise a solid material having a coefficient of thermal expansion greater than that of the ceramic material.5. The component of claim 1, wherein the inclusions have a decomposition, melting or evaporation temperature that is at or below a maximum ceramic material processing temperature.6. The component of claim 1, wherein the inclusions are decomposed, melted or evaporated when the ceramic material is processed to form voids in the thermal barrier coating.7. The component of claim 1, wherein a maximum ceramic material processing temperature is equal to a sintering step temperature that cures and densities the ceramic material.8. The component of claim 1, wherein a sintering step temperature is 1,000° C. above a stress free temperature of the ceramic material.9. The component of claim 1, wherein the coefficient of thermal expansion of the ceramic material is 10e?6K?1.10. The component of claim 1, wherein the coefficient of thermal expansion of the inclusion is twice the coefficient of thermal expansion of the ceramic material.11. The component of claim 1, wherein the inclusions comprise a polymer, ceramic or metal.12. A thermal barrier coating comprising:a layer of a ceramic material having a free surface; a plurality of inclusions having a coefficient of thermal expansion greater than that of the ceramic material disposed below the free surface of the layer of ceramic material; and a plurality of cracks extending from respective ones of the plurality of inclusions to the free surface. 13. The thermal barrier coating of claim 12, further comprising:the ceramic material comprising one of the group of alumina, zirconia, yttria-stabilized zirconia, and magnesia-stabilized zirconia; and the inclusions comprising a material having a coefficient of thermal expansion greater than that of the ceramic material. 14. The thermal barrier coating of claim 12, wherein the inclusions comprise a solid material having a coefficient of thermal expansion greater than that of the ceramic material.15. The thermal barrier coating of claim 12, wherein the inclusions comprise a hollow material having a coefficient of thermal expansion greater than that of the ceramic material.16. The thermal barrier coating of claim 12, wherein the inclusions have a decomposition, melting or evaporation temperature that is at or below a maximum ceramic material processing temperature.17. The thermal barrier coating of claim 12, wherein the inclusions are decomposed, melted or evaporated when the ceramic material is processed to form voids in the thermal barrier coating.18. The thermal barrier coating of claim 12, wherein the inclusions comprise voids.19. A thermal barrier coating comprising:a layer of a ceramic material having a free surface; a plurality of stress relieving cracks extending from the free surface into the ceramic material, the cracks extending into respective voids formed from inclusions having a coefficient of thermal expansion greater than that of the ceramic material and disposed within the ceramic material below the free surface so that the cracks have no crack tip, the voids acting as respective crack arrestors within the ceramic material. 20. A thermal barrier coating comprising a top free surface divided into segments defined by a plurality of cracks extending from the top free surface into the thermal barrier coating to respective crack-arresting inclusions having a coefficient of thermal expansion greater than that of the ceramic material and disposed below the top free surface.21. The thermal barrier coating of claim 20, wherein the inclusions comprise voids.22. A thermal barrier coating comprising:a layer of ceramic material having a free surface; a plurality of inclusions disposed within the ceramic material below the free surface; and a plurality of stress relieving cracks each extending upward from a respective one of the inclusions to the free surface but not extending downward from the respective one of the inclusions into the layer of ceramic material so that the plurality of stress relieving cracks each have no crack tip within the layer ceramic material, wherein the inclusions comprise a material exhibiting a coefficient of thermal expansion that is greater than a coefficient of thermal expansion of the ceramic material. 23. The thermal barrier coating of claim 22, wherein the inclusions comprise voids.