Building materials industry
Building materials industry is an important material industry in China. Building materials products include building materials and products, non-metallic minerals and products, inorganic non-metallic materials, three categories, are widely used in construction, military, environmental protection, high-tech industries and people's lives and other fields. It has played a huge role in promoting the development of the national economy
The term ferrous metals is used for all those alloys having iron as the major constituent. Pure iron is a relatively soft material and is hardly of any commercial use in pure state. Alloys of iron with carbon are classified according to their carbon content: Steels with 0.02 - 2 % carbon and Cast Irons with 2-4 % carbon.
Ferrous metals account for about three quarters of the metal tonnage used throughout the world. Steels can be further sub-divided into a number of categories. The term carbon steel is used for those steels in which essentially just carbon and iron are present. The term alloy steel is used where other elements are included. Typical alloying elements include manganese, aluminium, copper, nickel, chromium, cobalt and so on. Stainless steels are one form of alloy steels, which have high percentages of chromium and nickel in its chemical composition for their high resistance to corrosion. Due to their good strength, and relatively low cost, steels are widely used in many different applications including construction, transport, general engineering and consumer products.
Cast Irons as the name implies have been developed for casting process and the terms refer to a family of alloys including gray cast iron, ductile iron, white and malleable iron.