Steel structure

What is the steel?
The steel is an alloy consisting almost entirely of iron. It also contains small quantities of
carbon, silicon, manganese, sulfur, phosphorus, and other elements. Carbon is the material
that has the greatest effect on the properties of steel. The hardness and strength of steel
increase as the carbon increased. However, more carbon will cause steel to be more brittle
and will adversely affect its weldability. If the carbon content is reduced, the steel will be
softer and more ductile, but also weaker. The addition of elements such as chromium, silicon ,
and nickel produces high strength steel but the steel will be more expensive and not as easy
to fabricate.
The steel is manufactured in special process (extraction from the earth, melting in high
temperature, casting, ….etc.). Today, most the structural steel shapes and plates made by
melting scrap steel ( junk cars, scrapped structural shapes, discarded refrigerators, motors,
…etc

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