describe in detail the commercial forms of iron

Different commercial form of Irons are :-

1. Grey Cast iron: - It is fundamentally an alloy of iron, silicon and carbon. Cast irons are available with a wide range of properties. Pig iron are also referred as cast iron, chiefly because these forms of irons are not plastic enough even when hot to be forgeable; therefore they are always produced commercially by a process of melting and casting into shape, the commercial form of each of these metals is in casting.
2. Wrought iron: - It is the oldest form of iron made by man. It was originally produced by slow reduction of the metal from the ore in the forge fire. This reduction process resulted in a very impure iron which required further refining by mechanical working, which is by hammering or shaping to the form in which it is used. Wrought iron is a metal containing high purity iron and iron silicate in physical association. It is very low in carbon and the iron silicate or slag is distributed throughout the base metal in fibers which gives it a woody or fibrous appearance when fractured.
3. Steel (Master metal) : - Its plasticity, whether at room temperature or at elevated temperatures, allow it to be worked either hot or cold. Its combination of strength with plasticity makes it the most important metal for use in large structures. By varying the carbon content and by suitable heat treatments, we can alter the properties from a very soft workable steel of the type used in pressed metal parts, wires and different machinery.