An alloy of carbon and iron, steel is being widely used in the present day scenario. Various qualities like versatility, strength, and cost-effectiveness make it one of the most used metals in the contemporary world. However, the process of manufacturing steel runs much deeper than the finished product – it involves multiple steps and different methods make different grades of steel. The manufacturing process has significantly evolved over the years. However, it still employs the original Bessemer process to some extent, which uses oxygen to lower the carbon content in iron.
Let’s understand the manufacturing process in detail.
The definition of steel is ‘iron alloyed with carbon, usually less than 1%’. The carbon percentage varies from 0.25% to 1.5%.
The process to produce steel first requires the production of molten iron. The same is accomplished with the Blast furnace process. A furnace is an enclosed cylindrical structure that is used to heat materials to extreme temperatures.
The blast furnace is supplied with iron ore, coke (also known as crude iron – it is a grey and hard fuel manufactured by heating coal in the absence of air. It has high carbon content and a few impurities) and small quantities of fluxes (minerals like limestone which combines with impurities to form slag and separates from metal in the form of stony waste matter). The same results in the formation of molten pig iron, which is further required in the manufacturing of steel.
Passing oxygen through molten pig iron lowers the carbon content of the alloy and changes it into steel.
There a few properties which make good quality steel stand apart, like the following:-
1. They are corrosion resistant
Different types of steel have diverse levels of corrosion resistance. Some grades of austenitic stainless steel have great corrosion resistance because of the high amounts of chromium and molybdenum present in them. Also, apart from being resistant to rust, the various grades of quality steel guard against the corrosive effects of saltwater and chemical exposures.
2. They are heat treatable
Good quality steel is not affected when they are heat-treated and hence is widely used.
3. High strength
Good quality steel has high strength and hence is employed in various constructional purposes. The good quality steel has a strength ranging from 170 to 450 N/mm². The same makes them stand apart.
Along with all the above-mentioned properties, good quality steel also comes at a reasonable price, thus making it a preferred choice across industries.
5. Aesthetically pleasing
Quality steel is widely employed in interior designing and home appliances. The reason being they provide attractive finishing and are also durable.