Corner Treatment
When you flatten a sheet metal part by unsuppressing the Flat-Pattern feature, corner treatments are automatically applied to create a clean, flattened sheet metal part. The corner treatments are applied so the flat pattern is correct for manufacturing. To turn off corner treatments, right-click Flat-Pattern1, and select Edit Feature. In the PropertyManager, clear Corner treatment. Here is an example of corner treatments:

Model with a miter flange
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Flattened model without a corner treatment (using the Unfold feature)
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Flattened model with a corner treatment
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