Steel: from the extraction of metals to its recycling

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Steel is one of the most important materials for man. It is an alloy composed of two elements present in nature: iron and carbon. Both feature in a large number of products that we use every day: from cars to bicycles, household appliances to furnishing components, work tools to medical instruments, and also the infrastructures and the great works of mechanics. Since steel is a material of fundamental importance, its physical, chemical and mechanical properties have always been studied, and on the basis of these characteristics it is possible to choose the best material for every requirement.

We have gone beyond the study of these properties and tried to improve them by adding other elements (e.g. chrome, nickel, sulphur, etc.), thus creating different types of steel for multiple specific uses. It has been possible to respond with increasing precision to the needs of each sector, contributing significantly to human progress. The steel industry is committed to doing all this: starting from the extraction of the individual elements, to the processing of different steels with increasingly targeted formulations, to achieving the creation of high quality products for the most sophisticated uses.

In short, the different phases of the steel life cycle are as follows:

  • Raw material extraction: metal alloys such as steel are not available in nature; they are the result of a mix of pure elements. These are present in nature in various forms (e.g. iron ore) for which a series of chemical and physical procedures are necessary to allow their extraction.
  • Steel production: for all metal alloys, including steel, a series of operations (fusion, refining, alloying, casting, etc.) are necessary to produce the end product that has very different characteristics from those of the single elements that make it up. These operations result in steel having very different properties from its component elements of iron and carbon, making it suitable for the many applications for which it is designed, such as those where specific mechanical characteristics are required at high or low temperatures.
  • Manufacturing: the so-called semi-finished steel products (bars, bands, sheets) come out of steel mills and primary processing companies after stamping, cutting, shavings removal, welding and finishing operations, etc., giving life to the finished products put on the market.
  • Steel disposal and recycling: one of the key attributes of steel is that it is infinitely recyclable without losing its properties in strength, ductility or formability which marks steel recycling as a ‘closed-loop’: every component made with this material that is at the end of its life cycle is used to feed the new stages of production to return to the market in another form. What was a pot may find itself transformed into a car component, while what was a bicycle may be “reincarnated” as a power plant component.