It is expected that in construction there will become unexpected surprises and in one of those many unexpected surprises not many of the same long-term effects as the need to bend TMT bars. Bending TMT bar is a tricky skill, there are some obvious downsides such as broken TMT bars. The long-term negative effects come from the breaking of the protective film from the surface of the TMT bars. These films are coats of special paints which does rust or corrosion to happen. This happens as TMT bars have a strong shell and a soft inner core, while outer shell can withstand rust and corrosion for a long long time as they come prepared with a protective coating.
Bigger Problems with Bigger Grades
Now, there will confusion that saying that aren’t TMT bars supposed to be flexible? The answer to that question is that it is not necessary that all TMT bars need to be flexible. Depending upon the grade, the flexibility of the TMT bars differs. The TMT bars of the higher grade such as 600 and 600D are bit incapable when it comes to bending, the point being specialist machines are needed to bend higher grade TMT bars. The bending of higher grade steel is more about the technique rather than brute strength. When done improperly, as the protective coating could break, exposing the TMT bar to rust and corrosion as explained above.
Simplicity Does It
When it comes to lower grade TMT bars, 415 and 500 are known for their bendability, this bendability is the same reason why they are more resistant to earthquakes and natural disaster of the same nature. Lower grade TMT bar of FE415 can be easily bent without expensive machines, their high bendability also means the protective coating is also flexible. This is one of the reasons why FE415 is perfect TMT bar for the common man, it walks the fine line between strength, bendability and ductility.