What Does Hot Rolled Steel Mean?
Hot rolled steel is a type of steel that is formed using the hot rolling process at a temperature above its recrystallization temperature. Steel is easier to shape at this elevated temperature. Compared to cold rolled steel, hot rolled steel typically does not require any post-forming heat treatment. Hot rolled steel usually has more mill scale than cold rolled steel.
Corrosionpedia Explains Hot Rolled Steel
Hot rolling is often the cheapest way to form steel because additional steps that cold rolled steel requires, such as annealing, are avoided.
A bluish iron oxide layer, known as mill
scale, forms on the surface of hot rolled steel due to the elevated temperature. Some
operations, such as welding, require removal of the mill scale before
they can be performed.
Hot rolled steel typically does not have the same tolerances when being formed as cold rolled steel due to the thermal expansion that occurs at the temperature required for hot rolling steel.
Hot rolled steel is available in many shapes, including round bars, sheets, plates, I-beams and channels.