While the method has changed over the past 2,500 years, steel is still made much the same way as it was in the people of India made it so long ago. Iron alloys make up the finished product known as steel if the carbon weight is less than 1.7 percent. If the carbon is higher, the mixture is known as cast iron. One thing is changing – researchers are building new types of steel by adding different alloying metals into the mixture.
A coke oven is a huge vessel that burns the impurities out of iron ore. The heat must become extremely hot, so the oven and door must withstand the tremendous heat and still maintain their structure. The coke oven door plugs allow for pouring impurities off the mixture as it floats to the top of the liquid iron.
The iron ore, coke, and some lime are next added to a blast furnace that allows the still imperfect metal to reduce the carbon percentage from around 5 percent down to the desired less than 1.7 percent. If the impurities were left in the steel, the hardened metal would be brittle and unworkable. When the metal is heated, the impurities float to the top of the furnace, and the plugs allow the impurities to be poured out.
A specific and known level of carbon is added back into the iron to create the mixture into steel. The steel is them poured from the oven, and once cooled, it can be shaped, rolled, coated, tempered, and galvanized according to what is needed at the time the metal is created.
Steel has always been useful to mankind, but it has only recently been available to create items of use for the average person. With all the new types of steel researchers are testing it will be interesting to see what they come up with in the next 50 years.