TMT bars or Thermo-Mechanically Treated bars are high-strength reinforcement bars having a tough outer core and a soft inner core. The very first step of the manufacturing process involves passing the steel wires through a rolling mill stand.

Strength of the bars are carefully controlled by optimizing the water pressure for their pearlitic core and tough surface of tempered marten site, thereby providing an optimum strength, ductility and toughness. TMT bars are widely used in general purpose concrete reinforcement structures, bridges and flyovers, dams, thermal and hydel power plants, industrial structures, high-rise buildings, underground platforms in metro railway and rapid transport system. TMT Bars are thermo-mechanically-treated through leading world's best technology for high yield strength. The process involves rapid quenching of the hot bars through a series of water jets after they roll out of the last mill stand. The bars are cooled, allowing the core and surface temperatures to equalize. The bar core cools down slowly to turn into a ferrlite-pearlite aggregate.