Steel Sphere

This sphere is made from steel. The surface is specked with rust where the iron has combined with oxygen in the atmosphere. The majority of the surface is highly reflective and silver-coloured. Steel is predominantly made of iron, and contains a small amount of carbon, somewhere between 0.2 and 2% by weight. Other alloying elements may be added, including manganese, chromium, vanadium, and tungsten. As a pure substance, iron is quite weak. The alloying elements harden iron as they become embedded in the crystal lattice and prevent dislocations in the lattice from propagating. Varying the type and amount of alloying elements allows fine control over the material properties of steel, such as hardness and ductility. This means steel is a very versatile alloy, and exists in over 3500 different forms, which depend on the alloy, how it is made and how it is treated. Steel balls are vital for many types of engineering machinery acting as bearings and in rollers.