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ATLAS TMT bars are the new generation and high strength
ribbed reinforcement bars having superior mechanical properties in
strength, weldability, ductility, and bendability, meeting
International quality standards. ATLAS TMT bars are
produced in state-of-the-art manufacturing plants under close
supervision of our experienced frontline engineers and
metallurgists. ATLAS TMT bars have a uniform and
concentrated hardened periphery, with a softer core that has the
desired tensile strength coupled with high elongation, specially
required in seismic zones.
Under thermo mechanical treatment (TMT), our steel bars are passed
through a specially designed water-cooling system where they are
kept till the outer surface of the bars becomes colder while the
core remains hot. This creates a temperature gradient in the bars.
When the bars are taken out of the cooling system, the heat flows
from the core to the outer surface, further tempering of the bars,
which helps them attain higher yield strength. The resulting
heat-treated structure imparts superior strength and toughness to
the bars. The microstructure of the core is a very fine-grained
ferrite and pearlite. At ATLAS
TMT, the production of high quality TMT bars depends on three major factors -
Quality raw material, which is ensured through an extensive
vendor selection process
- Advanced & technically designed automated manufacturing mill
- Well-designed quenching and tempering technology
ATLAS
TMT bars are 'hot rolled' from steel billets/ingots and
then subjected to a PLC controlled on-line thermo mechanical
treatment in three successive stages QuenchingQuenching is generally done by cooling at a sufficiently high rate to avoid undesirable internal microstructure as well as to ensure uniform mechanical properties, minimize residual stresses, and avoid warpage. The experienced Quality Assurance & Control department at ATLAS ensures that a uniform quench rate is maintained along with required agitation near the surfaces of the parts, thus avoiding residual stress and warpage of the parts, and ensuring highest quality ATLAS TMT bars in the industry.
TemperingTempering is done to toughen
the metal by transforming brittle martensite into tempered
martensite. As the bar leaves the quenching box and is subjected to
air-cooling, the core remaining hot compared to the outer surface
allows heat to flow to the surface, causing tempering of the outer
martensitic layer into a structure called Tempered Martensite. At
ATLAS, we ensure precise control of time and
temperature during the tempering process, which results in our
ATLAS TMT bars with well balanced mechanical properties. Atmospheric Cooling
This takes place on the cooling bed where austenitic core is
transformed into a ductile ferrite-pearlite core.
The final structure consists of an optimum combination of a
strong outer layer (tempered martensite) with ductile core (ferrite-pearlite),
giving ATLAS TMT bars a unique combination of
higher strength and ductility |
