TMT Saria
The TMT bars production has increased due to the Government's initiatives. In FY 2018 the TMT bars made up 44 MnT of the 45.10 MnT steel products manufactured in India. The TMT bars are widely used in construction due to their high strength, ductility, and durability.
The TMT bars were first manufactured in 1800 in America and Great Britain. It led to various social and economical and cultural changes and the first step towards industrialisation started. Next with the invention of the steam engine steel became the centre of modern civilisation. Nearly 200 years later steel still continues to be important for a country’s economic development.
In India steel production started in 1874 in West Bengal by Bengal Iron Works (BIW). However, the historical moment in the Indian Steel industry was when the Tata Iron and Steel Company (TISCO) was inaugurated in Jamshedpur by Jamshedji Tata in 1907.
In the initial days the mild steel bars were used as the reinforcement to concrete. This trend continued till 1960 and the mild steel TMT Saria bars came with a tensile strength of 250 Mpa. As the construction methods and technology advanced with time there was a demand for much better and stronger reinforcement bars.
In the next two decades, there were great technological advancements to manufacture stronger reinforced steel bars in India. The Thermo Mechanical Treatment (TMT) was one of the innovations that pushed the Indian TMT industry into modernisation.
The TMT bars were first introduced in 1979 with IS: 1785:1979 and their grades were Fe 415 and Fe 500. In 1985 a higher grade of TMT bars was introduced in the market. Since then the demand for TMT bars has risen in the Indian construction industry. In 2008 the Fe 600 grade of the TMT bar was introduced with IS:1786:2008. The TMT industry has been contributing to the country’s economic development.
Key features of TMT bars
The ‘Thermo Mechanical Treatment’ manufacturing method gives the bars their unique properties. In this the bars are first heated to a high temperature and then cooled rapidly. This gives the bars a hard outer layer and a soft inner core.
The TMT bars are made using virgin iron ore and pure steel which gives them high tensile strength. The bars have features like greater elongation, uniform stress-bearing capacity, unbeatable ductility and superior bonding with concrete.
Greater elongation means that the bars can bear heavy weight, stretch under pressure and return to their original shape and size. The bars can withstand extreme pressure and not fail as they have a uniform stress-bearing capacity.
The bars are ductile which means that they will bend and not break when exposed to seismic forces like an earthquake. The bars can absorb the huge amounts of energy released during an earthquake and prevent the structure from collapsing.
The bars have a ribbed surface along their length and this provides superior bonding with concrete. The concrete does not crack or get dusted off with wear and tear. The structures become unbreakable for years to come.
