Are TOR, TMT and QST Steel Bars the same?
TOR
TOR steel is the generic term used to refer to reinforcement steel. It is actually a brand name of steel produced by Toristeg Steel Corporation of Luxembourg, or TOR for short. Because of the brand's popularity people still refer to regular cold twisted deformed bars as TOR steel, but this is incorrect use of the name.
CTD
Cold Twisted Deformed is a high-strength steel bar which is twisted resulting in ribs and lugs on the surface. This texture on the surface enhances the grip that concrete has with the bar in comparison to a smooth bar, and prevents slippage.
TMT
Thermo-Mechanically Treated bars undergo a process of quenching and tempering, which results in a tougher outer surface but retains a ductile inner core. The combination results in a high tensile strength with flexibility.
QST
Quenched Self-Tempered is a process where the heated bar is rapidly cooled, then reheated and allowed to cool naturally to create a fine-grained microstructure.
TOR/CTD | QST | TMT | |
Strength | Regular | High | Highest |
Ductility | Regular | High | High |
Cost | Regular | High | Highest |