Constructing buildings is not an easy task, It requires a lot of resources, technical skills, dedication and commitment. When we talk about the resources, the most vital components for constructing buildings are reinforced steel and concrete. Reinforced steel is primarily known for its excellent strength and ductility which provides the necessary strength to withstand the load of the structure. However, there are several factors that can affect the strength of the steel in such a way that it becomes extremely dangerous to the whole structure, and one such factor is rusting.
We all know what is rusting and its consequences. In the case of reinforced steel, getting rust is definitely not a good thing. Rusting is a chemical process that happens under the right circumstances i.e when iron and oxygen react with water or moisture. In the present scenario, there has emerged a trend for using rustproof TMT bars, which claims that it effectively prevents rusting. Many people actually believe this fact, but the truth is, it is just a misconception.
In the current market scenario, there has been a steel bar that is claimed to be rust proof. The important thing to know about this is there are no proven foolproof steel TMT bars. Metals like Iron and its alloys particularly steel will rust if left unchecked in the presence of oxygen and moisture. The rusting process is a combustion reaction, like fire, although, the reaction is much slower. Factors like water and salt can speed up the rusting process. Although rust formation cannot be completely avoided, it can be delayed by using certain measures.
There are ways in which the formation of rust can be delayed for a certain period of time. The TMT Steel bars are known for their excellent tensile strength and ductility. They are manufactured by a unique three-stage process called QST process. The three stages are quenching, self-tempering and annealing. Quenching involves rapid cooling of the bar using a series of water jets at different pressures at different places. Self tempering involves the transfer of heat from the core to the outer layer, thus making it harder. Annealing involves the cooling of bars at atmospheric temperature.
Quenching is considered the important process in producing TMT steel because it results in the formation of a hardened outer layer called “martensite” by rapid cooling. This outer layer not only provides high tensile strength, but it also provides high resistance to corrosion, which is caused by rust.
Other measures to protect TMT bars
The TMT steel is very strong and durable, even though it has high resistance to corrosion, there’s still a chance for corrosion to occur. The formation of rust can be minimized by following steps such as storing the TMT bars at sheds where it does not come in contact with water. Another way is to apply a coat of paint or chemical substance like epoxy coating.
By coating the TMT bars, it forms an envelope over the bar which prevents the bar from reacting with oxygen and water, but the catch is that if the coating goes off the bar at any point, that area will become exposed and start to rust. Concrete is used for the coating of reinforced steel bars, However, things do go wrong and concrete promotes rust if the salinity content in the concrete is quite high.
Things to remember
As mentioned above complete rust proof TMT bar is not possible in a structure because these measures can only delay the formation of rust to a specified period of time given if the structure is well maintained and the materials used are of premium quality. Therefore when purchasing the TMT bars, the brand is important but always check that the company is a reputed one and has a good track record in producing and distributing steel bars.