TMT stands for Thermo Mechanically Treated. The TMT bars have a hard outer surface and a softer core. Their manufacturing process includes hot rolled steel wires passed through water. This makes the surface hard and keeps the core warmer and softer. This helps in making the steel corrosion resistance and also increase its weldability.
On the other side, In HYSD steel manufacturing process the rod is strength deformed by application of stress after rolling so there are residual stresses at the grain boundaries and within the grains too. These sites of residual stresses are more prone to plastic deformation and corrosion.
Till 2005 to 2006, HYSD was widely used as rebars in building structures. Since the mass commercialization of TMT steel, HYSD is mostly not prefered today due to the unbeatable advantages of TMT has over HYSD.
Why TMT not HYSD?
- TMT bars do not surface flaws when compared with HYSD bars as unlike HYSD bars, as the manufacturing process in the TMT bars does not involve twisting or torsional stress.
- TMT Bars consume upto 17% to 20% less amount of steel than HYSD Bars.
- TMT bars come with a stronger external layer, something which is missing in HYSD due to ductile nature of the core and hard crystalline surface of TMT steel.
- When compared with TMT bars, HYSD bars cannot provide flexibility and ductility, thus limiting their use in different types of construction works.
- TMT bars are effective in earthquake- prone areas and withstand better with sudden earthquake schoks and absorption when compared with HYSD bars.
- TMT bars are lighter in weight compared to HYSD bars, so the transportation cost of TMT bars are low.
- In HYSD Bars residual stress is high and tensile strength is low that causes deformation. In TMT Bars residual stress is low and tensile strength is high for which it do not undergo any deformation.
- TMT bars are more corrosion resistant when compared with HYSD bars, due to the following reasons-
Rapid quenching and tempering used in TMT bar manufacturing process.
Low intake of carbon, sulphur & phosphorus TMT Bars are highly resistant to corrosion.
To provide you the highest quality of TMT products, Tufcon family has wide range of TMT products made by German Tempcore Technology to offer you. We manufacture TMT products like- billets, TMT bars, nails, binding wires etc which are widely used in modern construction projects. Contact us now to explore the strength of Tufcon TMT bars.