Steel is probably one of the most important metals in the history of the twentieth century, and probably the most important in the XXI century.
Their aesthetic, with its characteristic brightness and hardness and corrosion resistance make it an ideal material for both construction and industry.
Being one of the metals with less seniority, is one of the most important metals present in the world.
Steel is an alloy of iron and carbon, which carbon is present in a percentage less than 2%.
The steel manufacturing process begins with cast iron, removing its impurities of this, and reducing the percentage of the principal component of the alloy that is coal.
The main difficulty in the manufacture of steel is its high melting point, 1,400 degrees C, which prevents the use of fuels and conventional ovens. In 1855, Henry Bessemer developed the furnace or converter that bears his name and where the refining of iron was carried out by jets of pressurized air that is injected through the molten metal. In the process, gas is preheated by a regenerative process that allows temperatures of up to 1,650 degrees C.
Alloy steels have not only more steel manufacturers desirable physical properties, but also allow a greater range in the heat treatment process, which increases its potential in many fields of industry and construction, with applications as diverse as steel pipes or steel fittings for glass.
Here we can analyze some elements that can be used for steel alloys:
Chrome: the addition of the chromium element causes the formation of various chromium carbides that are very hard. However, the resulting steel is more ductile than steel of the same hardness produced simply by increasing carbon content. The addition of chromium extends the critical temperature range.
Nickel: the addition of nickel to the steel expands the critical temperature and does not form carbides or oxides. This process increases the strength without reducing ductility. Chromium is often used along with nickel to obtain the toughness and ductility provided by the nickel and wear resistance and toughness provided by the chromium.
Manganese: Manganese is added to all steels as deoxidation and desulfurization agent, but if the manganese content exceeds 1%, the steel is classified as a manganese alloy steel. Reduces the critical range of temperatures.