Crack Characterization Using Image Analysis

The microstructual characterization of thermal barrier coatings (TBC's) has been an important component in understanding the quality of the coatings and thus the ultimate performance in resisting metal substrate degradation in service. The focus of this paper is the characterization of cracks which may be a component of successful coating performance There are many ways to quantify crack morphology including orientation, actual length, number density, thickness, and overall horizontal and vertical length. However, a more complete characterization should include the determination of the degree to which a crack is perpendicular to the interface (vertical cracks).