Biaxial curvature due to film cracks

The resulting curvature changes of the substrate corresponding to these film 

Note that the curvature change in the a —direction always decreases due to crack formation whereas the curvature change in the y—direction can either increase or decrease, depending on whether is smaller or larger than Note that for widely spaced cracks with p/h 1, 

Notice that differences in elastic constants between the film and substrate are included in (3.108) and (3.109) through , as well as through the explicit dependence on the Poisson ratios. 

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