1. Definition of steels

The typology of steel products is the result of a long historical evolution, but also of a continuous renewal of steel supply, in response to user needs. When steelmakers talk about markets, they mean the downstream end of the value chain, as opposed to the upstream end, where we find raw materials, for example. Continuity and permanent change are the invariants of this historical temporality.

The result of this long evolution is that steels constitute the largest family of metal alloys available to engineers and designers of manufactured products in today's technological episteme. Iron and steel have played this vital role for centuries, and no doubt will continue to do so for a long time to come.

• The classification of steel products reflects the stability of this technological episteme, i.e. both the techniques...