Thermal stress intensity factors for a normal surface crack in a functionally graded coating structure

The thermal fracture behavior for a functionally graded coating structure (FGCS) with a normal surface crack is studied. The thermomechanical properties are continuous across the interface. The surface crack may intersect the interface. In the analytical procedure, integral transforms and residue theory are used. Some samples with some representative thermomechanical parameters are analyzed and the corresponding thermal stress intensity factors (TSIFs) are calculated. It is found that the TSIF is greatly affected by the temperature conditions and thermomechanical properties. Moreover, the possibility for a surface crack to expand across the interface is discussed.