Steel is an alloy of iron and carbon. To make steel you have to firstly make iron. Iron is made by combining iron ore, sinter and coke. These materials are put into a Blast Furnace and fired. The process produces a molten liquid known as ‘hot metal’, which can then be used to make steel.
The ‘hot metal’ is mixed with scrap metal (iron or steel) and is processed using one of three methods: Basic Oxygen, Electric Arc or Open Hearth. The ratio of ‘hot metal’ and scrap varies depending on the type, quality and strength of steel required. In a leaflet produced by the British Steel Corporation entitled “Making Steel” it explains that the steel making process is not an easy one to describe “… there are many forms of [steel], each with its own specific chemical analysis to meet the various needs of hundreds of different applications.
There are soft steels, hard steels, springy steels, special electric steels and a host of alloys where iron is mixed with other metals to form a wide range of special and stainless steels.”
Once produced the molten steel is then cast into ingots, special castings or slabs.
Molten Iron © National Museums of Scotland