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Ferrous Metals: Definition And Properties

The main thing to know about metals is whether they are ferrous or non-ferrous. Once we have made the distinction, we can look at their different properties. In this article, we will talk about ferrous metals and their properties.

What set ferrous and non-ferrous metals apart is whether they contain iron or not. Ferrous metals are the ones that contain iron. They also contain tiny amounts of other elements and metals. Because of that, ferrous metals are characterized by being magnetic and being susceptible to correction.

In everyday life, we find ferrous metals in demolition sites and other such places where scrap metal is normally found.

Some of the main examples of ferrous metals are cast iron and steel.

For all of these metals, iron is the main component.

Here is the full list of ferrous metals with their properties:

Steel

Perhaps, the best known as metal is steel. Mostly, steel is made out of iron and carbon.

This mixture carbon is the element that hardens the metal.

Although there are other elements. For example, we find in tougher alloy steel, the following elements:

Other simpler versions of this metal suggest cast iron I just made out of carbon steel which has had some more carbon added to it along with a certain amount of silicon.

Normally, I and contains something between 0.03 and 1.7 percent of carbon at 4.5 percent for cast iron.

How is still produced? Usually, different kinds of melting furnaces are used in the production of steel. For example, Bessemer converters, crucibles, induction, electric-arc and open hearth melting furnaces.

Specifically, for alloy steel, induction and electric-arc furnaces are used.

The raw materials are put into the furnace you could make sure of the following materials:

  • Pig iron.
  • Iron ore.
  • Limestone.
  • Scrap.

Once in the furnace, all these elements are melted. Then, the resulting steel is put into a ladle and poured into molds or ingots.

The reason why this ferrous metal is made into ingots is that these can then be made into big bars with a rectangular shape that can, in turn, be reduced if necessary by rolling them.

When molds, instead of ingots, are used is because a specific design is necessary.

Cast Iron  

The way cast iron is produced is by melting the following raw elements in a cupola furnace:

  • Limestone.
  • Coke.
  • Pig iron.

Cast iron is brittle yet hard and it is mostly characterized by being a metal of high levels of resistance to wear.

Because of those characteristics, cast iron is mostly used in the creation of engines and other automotive parts and also in different machine tools.

Once the raw elements (limestone, etc.) are melted in a cupola furnace they are then poured into either alloy steel molds or sand.

If the goal is to make gray cast iron, then the molten metal must become solid and cool down (room temperature) in the open air.

But, if the point is to make malleable cast iron, then white cast iron is used. White cast iron is similar to gray cast iron, the only difference between the two kinds is that there are less silicon and carbon in malleable iron.

The annellation of white cast iron takes more than 150 always at high temperatures that oscillate between 1500 and 17º F (between 815 and 927 ºC). What results from that process is malleable cast iron.

Is there any difference between the properties of cast iron and carbon steel? Yes, because there is a difference in their structure and chemical makeup their properties are quite different. For example, the carbon in steel is solid (solid solution), and the graphite used is flaky in form. But the graphite use is malleable cast iron has a rounded shape (nodular solution).

Those differences also result in the fact that malleable cast iron has far more mechanical properties that gray cast iron does.

Iron Ore

In order to produce this ferrous metal, limestone and coke must be melted using a blast furnace.

The reason why a blast furnace is used is to remove all the oxygen and foreign matter from the limestone and coke. This is what is known as the process of reduction.

The purpose of using limestone is to create a liquid slag. Coke is, in turn, used as a supplier of carbon that is needed in order to both reduce and carburize the ore.

The whole process is as follows: the limestone, the coke, and the iron ore are placed in the top section of the blast furnace. Then, a rapid combustion takes place by introducing a blast of preheated air. The introduction of preheated air results in the chemical reaction whereby all the oxygen is removed from the iron.

Once the iron has melted, the molten slag (ash from the coke, limestone flux, and the compounds that have been formed by the reaction to the flux with all the different substances in the ore) floats on top of the iron liquid, which is heavier.

Each and every material present is then drawn out separately.

Wrought Iron

Out of all the different ferrous metals that we have seen so far, wrought iron is the one that is closest to being pure iron.

The process of producing wrought iron includes introducing pig iron in a puddling furnace. Then carbon and any other elements are carefully extracted so that what it remains is as close to pure iron as possible.

Wrought iron is mostly used for decorative purposes but it is not unusual to deploy it in making chains, barbed wire, and even furniture.

If there is one ferrous metal that most people are familiar with, no matter what background they have, that would be wrought iron because of its many everyday uses and almost ubiquitous presence.

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