What is it?

This defect looks like serrated edges on the coil’s edges, and can be continuous or spotty in nature. It is also known as cracked edge or edge cracks. Coil edges can get slightly damaged from handling, and become hardened prior to final temper rolling. The temper rolling process results in brittle edges that can crack open and result in a serrated knife type appearance on the coil side wall.

Sawtooth Edge