Coil Breaks are creases which appear as lines transverse to the rolling direction and usually extending across the width of the steel. The condition is considered unsightly moreso in sheet form but also in steel coil form. They are only a cosmetic defect. They are non-injurious and will not affect form-ability. Coil Breaks will not affect the integrity of formed parts. The presence of them is a clear indication of very formable and ductile material. We Purchase steel with coil breaks here at Surplus Metals Corp.
“Coil breaks are narrow, irregularly changing deformation lines on low carbon steel strips. They can appear in many metallurgical manufacturing processes, such as pickling, galvanizing, cold rolling, processing on slitting or cutting lines, etc. They cause difficulties in many steel plants, since they are considered as serious surface defects leading to esthetical problems on the end product. In this paper, the types, visual appearance and microscopic properties of coil breaks are investigated. The roughness and waviness of the break lines were characterised using a contact-type surface roughness tester, while the microscopic deformation lines were studied using Hirox and Zeiss optical microscopes. The location, arrangement and relation to the microstructure can help to understand the formation mechanism of these surface defects.”
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