Diameter

Hot Rolled Steel Bar

Hot rolled steel is formed by a metal rolling process in which the steel is pressed at a temperature above its recrystallization threshold. This makes the steel easier to form and produces a product that is easier to work with.
Hot and cold rolling
As mentioned above, hot rolled steel is formed when the temperature exceeds its recrystallization threshold. Cold rolling steel involves the opposite process. Cold rolled steel bars are formed when the temperature falls below the recrystallization threshold of the steel. Hot rolled steel is also generally less expensive to produce than cold rolled, and the product is easier to form than cold rolled. However, hot rolled steel shrinks during cooling, and the size and shape of the steel are more unpredictable than cold rolled steel.

Features of Hot Rolled Steel Bar

Hot rolled rebar has several beneficial properties, including:
Slightly rounded corners (due to shrinkage).
Slight deformation, cooling may leave a slightly trapezoidal shape instead of perfectly squared corners.
Surface scaling due to extreme temperature cooling process.