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As regards to its mechanical properties cast steel is in many ways superior to grey and spheroidal iron. Steel is foremost used as a material when a clear thermal or chemical resistance or high solidity is needed. Castings from steel are therefore mainly used in shipbuilding, in engineering, in the automotive industry and in plant construction. Further on, steel is well suitable for welding, is malleable and through special production procedures and after-production processes it can offer a high variety of materialsThe reason for exceptional characteristics of steels is the low share of carbon which is under 2.06 per cent.

But this low share of carbon has also its disadvantages: steel has a much higher melting temperature as cast iron which means we have special demands within the melting process. Further, the liquid steel is thicker as from cast iron; its characteristics with mould filling are not as favourable and it has about two per cent shrinkage rule.

These physical characteristics of cast steel call for extensive after-production treatments of the cast pieces. As a consequence of the unfavourable mould filling capability the parts need to be cut after moulding. Cast steel receives its mechanical characteristics mostly only after thermal treatment, as for example after tempering, annealing and similar processes.

Due to its high corrosion resistance duplex stainless steels are often used in areas where there is a permanent contact between parts and aggressive media as for example with crude oil or sea water.

The two-phase structure of duplex stainless steels which consists of a ferritic matrix with austenite pads produces a combination of characteristics of stainless chromium steels (ferritic or martensitic) and chromium-nickel steels (austenitic). This enables duplex steels to have a good ratio between strength and ductility. Furthermore they show high fatigue strength even under corrosive strain.

Due to its welding characteristics duplex stainless steel parts can be easily fitted into bigger assemblies.

As regards to its characteristics at high temperatures nickel base alloys are in many ways superior to steels.Nickel base alloys are in use mostly when a usage with extensive thermal resistance near the melting point is needed and/or we are working in carburization surroundings. Thus, components from nickel base alloys are mostly used in energy production, chemical industry, aviation and with oil and gas production.

Nickel base alloys tend to oxidise during the melting procedure, which is highly demanding for the technical procedure of melting itself. Furthermore, the molten mass of nickel base alloys is thicker as the molten mass of steel and it is more demanding when filling the casting mould.

Grey cast iron is the most frequent used iron-carbon alloy. Its unique characteristic is its high abrasion resistance and its good pouring capability. Also the material is easy to process and it dampens extremely well mechanic vibrations.

The reasons for these physical characteristics lie in the structure of the cast iron. Carbon in grey cast iron is found in blades, which form three-dimensional ramifications. Yet, this bladed graphite is also responsible for the very low ductility of the material

Spheroidal iron shows high ductility. And even more. It possesses an extremely high solidity, which is partly even higher than ductile and steel cast iron with identical ductility values.

An additional advantage of the material: through further alloying we can further improve abrasion resistance, heat and corrosion resistance.

Also for this the reason of the material characteristics lies in the structure of the iron-carbon alloy. The graphite shows a structure in the form of a small ball within the cast iron. Thus, spheroidal iron is also referred to as spherulitic graphite cast iron.

If one needs high resistance to corrosion, e.g. against the influences of sea water or against alkaline mediums, then the material Ni-Resist is highly suitable. Further Ni-Resist, also called austenitic cast iron, is non-scaling, resistant to erosion and is not magnetisable.

The reason for these characteristics is the high share of nickel of more than 20 per cent. Thus, Ni-Resist is often used in the areas of food industry, shipbuilding and medical engineering.

Examples for construction parts made of this material are pumps, valves, furnace parts, sockets, piston rings, compressors, turbo-charger casings, exhaust manifolds.