Edge curling

On a flat bed, the extent of edge curling is determined not only by the lateral shrinkage tensile force, but also by the weight of the carrier, the weight of the tape itself, and other stress-relief mechanisms in place. 

Disengagement from the carrier surface is typically called "selfrelease and is always preceded by edge curling. From Figure 4.26, any lateral shrinkage stress will cause various effects on the tape. 

Flaking Peeling away of a hard and brittle surface upon cracking. The edges curl away firom the surfoce and create a flaking tendency. 

If the tensile stresses are isotropic, the microcracking will be in the form of a dried mudflat cracking pattern, often with the edges curled away from the substrate. If the stresses are anisotropic, the pattern will be modified perhaps to an array of linear failures, as shown in Figure 12.2. 

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