What is CTD Steel Bars?

CTD rods are called as Cold Twisted Deformed. The method of twisting the rods generaly increases the tensile strength of rods. Here twisting of steel rods is done after it gets cooled. Here atn this time the topmost and near topmost fibres are getting ruptured while it is twisted, which ends in the formation of micro cracks over the surface of the finished steel rods. If these cracks are carefully seen in microscope the width of cracks is more at the topmost fibre and gradually reduces when it goes deeper into the section. These cracks acquires water or water molecules which are harmful to steel or it may be the major cause for RUST. Hence the use of CTD rods are not advisable.