THERMEX, The Licensed Technology

The basic QST process and subsequent improvements are patented worldwide. Due to its simplicity and ease-of-operation, THERMEX QST Technology gained immediate global acceptance. Rolling mills are authorized to use Thermex Technology, only on a License basis. It is mandatory for all Thermex licensees, to obtain all critical and proprietary equipment for the Thermex QST System, from H&K India. This reduces the start-up time without compromising on the quality. The desired Thermex rebar properties are also established right from the day “one”.

TMT is not a brand, but the generic name given to rebars produced using a general rolling and quenching process. Many rolling mills do not have a proper quenching & self-tempering system. Hence the rebars produced through such systems don’t necessarily comply with BIS and International standards.

BENEFITS OF steelmax-tmt

steelmax-tmtBars have superior weldability which helps the architects and designers to build innovative and creative structures without affecting the quality of construction.


THERMEX Quenching & Self Tempering (QST) Technology and state of the art manufacturing process ensures a minimum elongation of 18-20% for steelmax-tmt, which is 50% more than the basic BIS requisite. This extra elongation turns out to be extra beneficial for "ductility properties" in seismic-resistant structural design.


steelmax-tmtBars have a great degree of elasticity. The soft ferrite-pearlite core of the TMX bars gives them superior bendability. These bars can be easily bent and molded into any shape. All the STEELMAX TMX bars undergo “bend test” and “re-bend test” as per the BIS Norms.


steelmax-tmtBars are highly ductile and have a super-strong surface layer. These properties help in withstanding fatigue for a longer period. Fatigue strength is the highest stress that a material can withstand for a given number of cycles without breaking. Fatigue strength is affected by environmental factors, such as corrosion. The enhanced elongation translates into greater ductility, which gives the resultant structure improved resistance during earthquakes and other natural calamities.


STEELMAX TMX Bars are produced in FE500, FE500D, FE500S, FE550, and FE550D grades. However, STEELMAX maintains lower levels of carbon, sulphur, and phosphorus than the specification, resulting in EXCELLENT DUCTILITY, HIGH BENDABILITY, and BETTER CORROSION RESISTANCE AND SUPERIOR WELDABILITY.


steelmax-tmtBar uses low alloying elements like Chromium and copper (combining to above 0.40%) to improve corrosion resistance properties and other mechanical properties.

  • Chromium is combined with steel to improve its resistance to oxidation. Chromium prevents iron from oxidation by oxidizing first and forming a protective layer over the steel. Chromium also helps to improve mechanical properties, even in smaller amounts. It will increase the steel’s strength, hardness, and ability to be heat treated. Improves UTS/YS stress ratio.
  • Copper is beneficial to atmospheric corrosion resistance when present in amounts exceeding 0.20%. Steel resistance to atmospheric corrosion is also called weathering steels. Copper is added to steel in the form of pigs, refined ingots, or as copper and nonferrous alloy scrap. It also enhances the mechanical properties of steel.

Although steel and concrete are two different materials they have to behave like a single unit in a reinforced structure. This can only happen when the concrete grips the steel bar from the strongest bond through the unique rib pattern of the rebar.  the bar uses a rib pattern that uses in B500C rebars in British standards where the ribs shall alternate between a higher and lower angle with respect to the bar axis which yields a better bond strength.  bars maintain the bond requirement more than as specified in the standard which increases the bond strength better with the concrete.

Remarks: RELATIVE RIB AREA (RRA) is the area of the projection of all ribs on a plan perpendicular to the longitudinal axis of the reinforcement steel divided by the rib spacing and the nominal circumference. It is not a part of BIS standard specification and applicable to British standards only.


steelmax-tmtBars are produced as per IS 1786:2008 and as per the new BIS product manual July 2020 with new six-digit Marking on the product for Customer Identification and other markings as per BIS Guide lines.


Due to high UTS/YS ratio(The higher UTS/YS Ratios is one of the important parameters for seismic resistance in steel reinforcement bars used in construction. It enhances the energy absorption capacity of steel before failure)and better elongation percentage, the STEELMAX BARS’ bendability and earthquake resistance properties are very high and guarantee high-level safety for ages. Bendability is very high which has an obvious advantage in the construction site