TMT bars in modern-day construction are indispensable. Engineers and developers rely on TMT bars for the strength and longevity of the construction. However, there are a few different grades of TMT bars available in the market. These grades of TMT bars are invented by combining different components and changing their percentages in the composition. The reason for making different grades of TMT bars was to increase the strength and ductility of the TMT bars. Fe 500 TMT bar and Fe 550 D TMT bar are two different grades of TMT bars and have some differences. Let us check how they differ from each other in this article.
Fe denotes iron, and 500 denotes the strength of the bar, which is 500 MPa. That means the minimum yield strength of this TMT bar is 500, and the tensile strength (fu) is 545 N/mm2. This is a variant of TMT bars and is made with iron, sulfur, and phosphorus, like other TMT bars. However, the ratio of the core components differs for each type of TMT bar. Fe 500 TMT bars are ideal for small to medium-sized constructions because of their strength.
Fe 550D TMT bar is also made with the same core elements mixed in different ratios. Here, Fe denotes iron, 550 denotes strength, and D stands for superior ductility. Fe 550D TMT bar has a yield strength of 550 and an ultimate tensile strength (fu) of 585 N/mm2. There is no doubt that the Fe 550D TMT bar is more ductile and stronger than the Fe 500 TMT bar. It is ideal for bigger constructions.
Despite having the same core elements, Fe 500 and Fe 550D TMT bar have many differences. Let us check them closely in this section.
Fe 550D TMT bar has iron as the main element. Which is mixed with carbon (0.25%), phosphorus (0.04%), sulfur (0.04%) materials by mass, and S+P is about 0.07%.
Fe 500 TMT bar is made of iron mixed with carbon (0.3%), phosphorus (0.055%), sulfur (0.055%), materials by mass, and S+P is about 0.105%.
Fe 500 TMT bar is strong, but Fe 550D TMT bar is capable of handling more pressure with superior strength.
Fe 550D TMT bar is more ductile than Fe 500. That is why Fe 550D can handle more pressure without permanent deformation or breaking.
Fe 500 TMT bars are better for strong welding joints. On the other hand, Fe 550D TMT bars are stronger, and it’s harder to weld into joints.
Fe 550D TMT bar is better at handling pressure and earthquakes due to its superior strength and ductility. Fe 500 TMT bars are a bit weaker than Fe 550D, and that is why it is not ideal to use in construction in earthquake-prone areas.
Due to better strength and ductility, Fe 550D TMT bar is used in large constructions like dams, bridges, huge commercial and residential complexes, etc. Fe 500 TMT bars are used in small to medium-sized constructions like small commercial and residential complexes.
Fe 550D TMT bar is costlier than Fe 500 TMT bars. However, the higher price of Fe 550D is justified by its superior features.
Both Fe 500 and Fe 550D TMT bars are made with the same core elements. However, due to the difference in the percentage of those elements and the making procedures, the feature of these two grade of TMT bars are a little different. Fe 550D TMT bar is costlier than Fe 500, but justifies its cost by superior ductility and strength.
