Iron melts faster when there will be low carbon in Iron.During steel making the molten Iron gets purified and alloying being done through the process. How the carbon is being controlled at Iron melting stage and what it is called?
It's not really that hard. You can use your charcoal grill to do it. First build a large fire in it and then bury the steel in the coals. It'll only take about ten minuites or so for the steel to heat through. Then pick it out of the coals with tongs and drop it into a bucket of water. Repeat as desired. Eventually it'll get as brittle as glass. To fix this, you must anneal the metal. Again heat the metal in the coals, only this time let it stay there until the coals go all the way out all by themselves. Next day when all the way cool, Take it out and clean it off. Viola!, you have hardened steel.
Steel is usually made in a two-step process. As you may know, carbon, in the form of coke, is added to the iron ore during the initial smelting process. This is the first step. The conversion of iron ore into raw iron is accomplished with a blast furnace. Carbon dissolves with the iron during the smelting process. The amount of carbon in the iron is generally not controlled at this point as this would be too difficult, the excess carbon is removed in the next step. The result is pig iron which is crude iron that has a very high carbon content, and a large amount of impurities. Pig iron is almost as brittle as glass, and it is useless in this form. In most modern steelmaking operations, molten pig iron is tapped from the blast furnace three or four times per day- it is not allowed to cool. The liquid pig iron is carried in ladles directly to a Basic Oxygen Furnace which converts the pig iron into steel. The basic oxygen converter uses a stream of pure oxygen to burn off the excess carbon. Impurities are also burned off, particularly phosphorus, silicon, and sulfur (which damage the steel's properties.) These elements all have a much higher affinity for oxygen than iron does, so the iron itself remains unchanged. Once the carbon content and the impurities are reduced to the desired level. The oxygen is shut off, and the iron has now become steel. At this point other alloying elements may be added, such as chromium, manganese, or molybdenum. These elements improve the steel's properties, but also add to it's price. If necessary, more carbon can be added as well if the carbon content has accidentally dropped too low. Finally, molten steel from the basic oxygen furnace is poured off. It can be cast into ingots, billets, or thin slabs.
