Specifications: a) Fe: 70% Min, P: 0.08 Max, S: 0 ... iron (2, 3) oxide, hematite and magnetite. Mill scale is formed on the outer surfaces of plates, sheets ... -chemically cathodic to steel, any break in the mill scale coating will cause accelerated corrosion of steel exposed at ... a days most steelsmills can supply their produce with mill scale removed and steel coated with shop primers over whichwelding ...