Types of TMT steel bar grades and their applications
The majority of modern structures get their strength from TMT bars. From dams to residential buildings, TMT steel bars are preeminent material for construction. So, if you are in search for the best TMT bar in Kolkata, the first and foremost thing is to understand the different grades of steel bars and their applications. The following information will help you avoid being subjected to fraudulent practices.
TMT steel bars are available in various kinds of physical properties and chemical compositions that account for diverse usage in construction. In this blog, we will discuss the variety of TMT steel bar grades along with their applications.
Different types of TMT steel bar grades
Fe-415, Fe-500, Fe-500D, Fe 550D and Fe-600 are the five types of TMT steel bar grades that most TMT bar manufacturing companies in India offer. The grade of TMT bars indicates their strength and rigidity factors. The number defines the minimum yield strength of a bar, and the letters with the number represent the elongation properties.
TMT bar grade | Adukia’s different grades of steel bars
Fe-415 TMT bar
Fe-415 is commonly used for small-scale constructions such as houses and residential projects. These TMT bars have uniform elongation that makes them resistant to earthquakes, hence they make the perfect choice for resisting damage from natural calamities.
Chemical composition
The chemical composition of Fe-415 is; Carbon- 0.30%, Sulphur- 0.06%, Phosphorus- 0.06%, and S+P- 0.110%. The mechanical properties of the Fe 415 grade bar are a minimum yield strength of 415N/sq.mm, along with an elongation of 14.5%.
Practical application
These TMT bars are appropriate for low-load construction in earthquake-prone areas. Apart from that, these are just the right fit for small-scale structures.
Fe-500 TMT bar
Fe-500 is one of the most versatile TMT bar grades, which finds its application in small-scale and large-scale constructions. These TMT bars offer good strength and ductility at the same time, making them a perfect combination for construction.
Chemical composition
The chemical composition of Fe-500 TMT bar is as follows; Carbon- 0.30%, Sulphur- 0.055%, Phosphorus- 0.055%, and S+P- 0.105%. With this chemical composition, you get a minimum yield strength of 500N/sq.mm and 12% elongation properties.
Practical application
The application of the Fe-500 TMT bar lies in residential, commercial, and multi-story buildings. The other variations of Fe-500 TMT is Fe-500S and Fe-500D. These bars have great tensile strength and high resistance to corrosion. As these bars have a great minimum elongation percentage and high ductility, they are ideal choices for underground construction and construction in high seismic activity areas.
Fe-550 TMT bar
Fe-550 TMT bars have high yield strength with specifications to ensure maximum savings on steel consumption. It has a minimum yield strength of 550N/sq.mm and tensile strength of 585 N/sq.mm.
Chemical composition
The chemical composition of Fe-550 TMT consists of; Carbon- 0.30%, Sulphur- 0.055%, Phosphorus- 0.050%, S+P- 0.100%, Manganese- 0.50%, Carbon Equivalent- 0.42%.
Practical application
These TMT bars are extensively used by marine and bridge construction companies.
Fe-550D TMT bar
With a significant difference in the properties, the Fe-550D TMT bars are different from Fe-550 bars. The “D” in these TMTs stand for high ductility, which gives the Fe-550D TMT bars an upper hand in absorbing energy.
Chemical composition
Manufactured using special technology termed direct quenching, the Fe-550D TMT bars are cooled after the final rolling stage. At Adukia Industries, we offer Ultramax Fe-550D TMT Bars that have a minimum yield strength of 570N/sq.mm and an ultimate tensile strength of 630N/sq.mm, and an elongation of 20%.
Practical application
The high ductility and elongation properties in these TMT bars make them the perfect choice for high seismic areas, as well as in areas that need high-stress endurance. High-rise buildings, bridges and flyovers, industrial sheds, dams, and transmission towers are some other areas of application.
Fe-600 TMT bar
Fe-600 TMT bars are known for their premium value and ultra-strength properties. These bars are designed to gracefully support the growing infrastructure and thrive in the seismic sensitive zone. As the yield quality is highest in Fe-600 TMT bars, the area or the steel required will be a lot lesser.
Chemical composition
The chemical composition of Fe-600 TMT consists of; Carbon- 0.30%, Sulphur- 0.04%, Phosphorus- 0.04%, and S+P- 0.075%. The chemical composition ensures the load-bearing capacity and strength of the TMT bar grade.
Practical application
These TMT bars are used for construction in mechanical zones, business properties, towers, plants, metro ventures, freeways, and more.
Here’s a table summarising the different grades of steel bars for your convenience:
| Grade | Yield Strength (N/sq.mm) | Elongation (%) | Chemical Composition (Max %) | Applications | Key Features |
|---|---|---|---|---|---|
| Fe-415 | 415 | 14.50% | C: 0.30%, S: 0.06%, P: 0.06%, S+P: 0.110% | Small-scale homes, residential projects, low-load & earthquake-prone areas | Good ductility, earthquake-resistant |
| Fe-500 | 500 | 12% | C: 0.30%, S: 0.055%, P: 0.055%, S+P: 0.105% | Residential, commercial, multi-storey buildings, underground & seismic-prone construction | Balanced strength & ductility |
| Fe-550 | 550 | – | C: 0.30%, S: 0.055%, P: 0.050%, S+P: 0.100%, Mn: 0.50%, CE: 0.42% | Marine structures, bridges, infrastructure projects | High strength, cost-saving |
| Fe-550D | 570 | 20% | Same base as Fe-550, but higher ductility | High-rise buildings, bridges, flyovers, dams, industrial sheds, seismic zones | Extra ductility, energy absorption |
| Fe-600 | 600 | – | C: 0.30%, S: 0.04%, P: 0.04%, S+P: 0.075% | Metro rails, towers, highways, heavy industries, mechanical structures | Ultra strength, steel-saving |
Conclusion
Choosing the right grade of steel bar can not only save your money but also increase the lifespan of your project. Adukia Industries is pioneering the manufacturing of TMT bars. With over 50 years of experience, we offer a range of the best TMT bars in Kolkata that consumers can rely on. Depending on the specific needs and requirements, one can select any of the TMT bar grades mentioned in the blog.
FAQs
Should I go for Fe 500 or Fe 550?
It depends on why you need the tmt bars. Fe 550 has higher ductility and strength than Fe 500, so, if you need more strength then go for Fe 550. But if you are working on a residential project, the Fe 500 TMT bar is a standard choice.
What is the reason behind grades in TMT bars?
The grade of steel bars defines their yield strength. It means how much stress the TMT bar can handle before it permanently deforms. For example, Fe 550 has a yield strength of 550 N/mm2, which means if you put stress over 550, it will lose its shape.
Why is sulphur used in TMT bars?
Sulphur is a critical component for increasing the machinability of TMT bars. It basically indicates how the steel can be shaped or cut by cutting tools. Though adding high quantities of sulphur can lower weldability and increase brittleness, using it in the right amount is advantageous.