Microalloying with Nb, V, Ti & B, in combination or individually helps in meeting most of these requirements and producing High strength reinforcement bars having yield strength of 500 and 550 MPa. Production of reinforcement bars by the addition of micro-alloys gives the desired results of high strengths but at a cost, which is prohibitive. Moreover, the achieved ductility is also low.

The need for cutting down the cost of production of high strength reinforcement bars initiated the involvement of a more economical and competitive process -- the so called Thermo Mechanical Treatment (TMT) Process. The Thermo Mechanically Treated bars are generally called TMT bars. These bars owe their advantage to their composite micro-structure, which is a soft and ductile ferrito-pearlitic core and a tough surface rim of tempered martensite.