Which element is alloyed with iron to form steel?

Steel is a metal alloy whose major component is iron, with carbon content between 0.02% and 1.7% by weight. Carbon is the most cost effective alloying material for iron, but many other alloying elements are also used. Carbon and other elements act as a hardening agent, preventing dislocations in the iron atom crystal lattice from sliding past one another.

Steel production at an integrated steel plant involves three basic steps. First, the heat source used to melt iron ore is produced. Next the iron ore is melted in a furnace. Finally, the molten iron is processed to produce steel. These three steps can be done at one facility; however, the fuel source is often purchased from off-site producers.

Cokemaking

Coke is a solid carbon fuel and carbon source used to melt and reduce iron ore. Coke production begins with pulverized, bituminous coal. The coal is fed into a coke oven which is sealed and heated to very high temperatures for 14 to 36 hours. Coke is produced in batch processes, with multiple coke ovens operating simultaneously.

Heat is frequently transfered from one oven to another to reduce energy requirements. After the coke is finished, it is moved to a quenching tower where it is cooled with water spray. Once cooled, the coke is moved directly to an iron melting furnace or into storage for future use.

Ironmaking

During ironmaking, iron ore, coke, heated air and limestone or other fluxes are fed into a blast furnace. The heated air causes the coke combustion, which provides the heat and carbon sources for iron production. Limestone or other fluxes may be added to react with and remove the acidic impurities, called slag, from the molten iron. The limestone-impurities mixtures float to the top of the molten iron and are skimmed off, see Figure 1, after melting is complete.

Sintering products may also be added to the furnace. Sintering is a process in which solid wastes are combined into a porous mass that can then be added to the blast furnace. These wastes include iron ore fines, pollution control dust, coke breeze, water treatment plant sludge, and flux. Sintering plants help reduce solid waste by combusting waste products and capturing trace iron present in the mixture. Sintering plants are not used at all steel production facilities.

Steelmaking with the Basic Oxide Furnace (BOF)

Molten iron from the blast furnace is sent to a basic oxide furnace, which is used for the final refinement of the iron into steel (Figure 1). High purity oxygen is blown into the furnace and combusts carbon and silicon in the molten iron. The basic oxide furnace is fed with fluxes to remove any final impurities. Alloy materials may be added to enhance the characteristics of the steel.

The resulting steel is most often cast into slabs, beams or billets . Further shaping of the metal may be done at steel foundries, which remelt the steel and pour it into molds, or at rolling facilities, depending on the desired final shape.

Carbon. Nickel or Chromium used to make Stainless steel

Carbon is added to pure iron to make it steel. The percentage of carbon content may be between 0.25 to 1.25%.

To make stainless steel some nickel and chromium are added to pure iron.

Carbon is the main constituent.Nickel and Chromium are also used to produce better quality steel.

Carbon

That's carbon who is the intermediate in steel iron process...!!!

Nickel or chromium with carbon

basicaiiy carbon but others like Al,Mn,Ni etc are also sumtimes added 2 improve its qualities

That'll be carbon.

few like...

carbon,

nickel,

chromium.