What is the Advantages of Iron?
For several reasons Iron is an incredibly useful substance:

• Using simple tools it's easy to refine iron.
• In the creation of electric motors and generators iron can be useful by magnetizing it unlike most substances.
• You can build things like engines from iron because it can handle heat unlike wood.
• Relatively speaking, and especially when compared to wood or copper, iron is extremely strong.
• 5 % of the Earth's crust is iron, so it's plentiful. Also in some areas as much as 70 % iron it's containing of concentrates ores.
• Iron is easy to shape and bend using simple tools only by heating it.

Iron has been useful to man for thousands of years. Because it's easier deal with than aluminum that must have access to huge amounts of electricity to refine it, and either cast it or extrude it to shape it. That's why aluminum really did not exist in any meaningful way until the 20th century. And iron was so important historically.

In primitive societies tools were available to create easily from iron such as the flintlock rifle that would be impossible to create without iron. Right now, the economic equation gives inexpensive iron and steel a huge advantage over much more expensive alternatives. But a day will come when we are so advanced technologically that aluminum, plastics and things like carbon and glass fibers will replace iron.

By painting, galvanizing , chrome plating or sacrificial anodes we can control rust that is the only problem with iron and steel.

What is Iron Ore?
Iron ore is a rock that happens to contain a high concentration of iron. And to make iron we start with it.

The availability of iron ore deposits in countries like England, the United States, France, Germany, Spain and Russia gave these countries an edge between the 15th and 20th centuries. And we can see the correlation when we think of the historical importance of all of these countries.

Common iron ores include (mixed into rocks containing silica usually)

• Hematite - Fe 2 O 3 - 70 percent iron
• Magnetite - Fe 3 O 4 - 72 percent iron
• Limonite - Fe 2 O 3 + H 2 O - 50 percent to 66 percent iron
• Siderite - FeCO 3 - 48 percent iron

How to Create Iron?
To create pure iron, you need to eliminate the oxygen the iron ores contain combined with iron

Bloomery is a primitive facility to refine iron from iron ore. It works in adding a good supply of oxygen (provided by a bellows or blower), with charcoal (essentially pure carbon) , iron ore, and burn it all. The carbon combines with oxygen to create carbon dioxide and carbon monoxide (releasing lots of heat in the process). Carbon and carbon monoxide combine with the oxygen in the iron ore and carry it away, leaving iron metal.

Because the fire does not get hot enough to melt the iron completely in a bloomery. We are left the bloom ( with a spongy mass containing iron and silicates from the ore). Wrought iron is made by mixing silicates into the iron metal while heating and hammering the bloom. And it's perfect for creating tools in a blacksmith shop because it's tough and easy to work with.

Blast furnace is an advanced way to smelt iron. It's charged with charcoal or coke (coke is charcoal made from coal), limestone (CaCO3), and iron ore. In the bottom of the furnace a huge quantities of air blast in. slag is formed when the calcium in the limestone combines with the silicates. A slag on top of the liquid iron will form the liquid iron flow out and cool, periodically.

Pig iron is a metal formed when a liquid iron flows into a channel and indentations in a bed of sand. Then it cools.

At the core of the blast furnace the temperature reaches almost 3000 degrees F (about 1600 degrees C), with 5 tons of air being consumed, half-ton of limestone, 2 tons of ore, and 1 ton of coke to create a ton of pig iron.

Pig iron is so hard and brittle almost useless containing 4 % to 5 % carbon

We can do one or two things with pig iron:

• Create steel .
• Create wrought iron that is malleable, bendable, wieldable and very easy to work with. By melting it, slag it, it to eliminate most of the carbon (down to 0.3 %).

How to Create Steel?
Impurities like silica, phosphorous and sulfur weaken steel tremendously, so it must be eliminated. Steel also has a consistent concentration of carbon throughout (0.5% to1.5%).
Steel advantage is greatly improved strength.

One way to create steel is the Bessemer process .

Another way to create steel from pig iron is the open hearth furnace. Iron ore, limestone, and pig iron heated to about 1600 F (871 C) ore go into an open hearth furnace. Ore and limestone forms a slag that floats on the surface. Impurities, including carbon, are oxidized and float out of the iron into the slag. Carbon steel is made when carbon content is right.

A basic oxygen furnace to create steel is used by modern steel plants, it's 10 times faster that the open hearth furnace.

To create different properties to steel we add a variety of metals. Such as creating a strong and light steel called chrome-moly steel, By adding chromium and molybdenum. And creating a steel resistant to rust, by adding 10 % to 30 % chromium.

A very lucky coincidence made it easier to move humans forward at a rapid pace. A huge availability of iron ore and vast quantities of oil, coal to power the production of iron Which made us get this far