Rails are not just steel beams; they are a high-quality and intricately crafted technical product. Because not every kind of steel is the same – rails are mostly made of steel – steel rails have a specific composition of different components to make the rails durable. The quantities of some additives can affect the properties significantly as a lot of research and manufacturing know-how has been put into the development of rails. There is only one thing that all steel rails have in common: they are made of rolled steel, even when the composition of the steel may differ.

The importance of rails as “special kinds of steel beams” can be explained with their main functions. Rails build the surface for railway vehicles to run on. On the bottom part of the rail, the rail foot transfers the loading and distributes the load to a bigger surface. Enormous forces can act in all dimensions. Both, in freight transport with high axle loads and in high-speed train traffic with very dynamic loads. Severe vertical forces act when a train runs around a curve. Even today, some tram systems have curves with radii lower than 15 m and in the railway sector curves can be found with a radius as small as 300 m. Of course, wear resistance and long life of the rails are of great importance, because rails must neither break nor be too soft. In spite of a comparatively minimal contact area of the wheels on the running surface of the rails, a frictional connection must be obtained without leaving any traces in the structure and surfaces.