Steel rebar is a steel material used for reinforced concrete and prestressed reinforced concrete. Its cross section is usually round, sometimes square with rounded corners. The main types of rebar include plain round bars and deformed bars. Plain round bars are actually small round bars and coils of ordinary low-carbon steel, while deformed bars have ribs on the surface, usually 2 longitudinal ribs and transverse ribs evenly distributed along the length. The shape of the transverse ribs can be spiral, herringbone or crescent.