Iron was one of the most commonly used metals of ancient
times. However, iron was very soft and brittle for many uses. Many people
looked for a stronger metal that could eventually be used for bridges, trains,
factories, and even jewelry!
The answer came in the form of an alloy. Let’s backtrack for
a second: a mixture is a combination of an elements and compounds, two or more
compounds, or two or more elements. An alloy, specifically, is a mixture of a
metal and other elements.
So which alloy would be the answer to a stronger, more
efficient metal?
Steel, of course!
So what is steel exactly? The primary part of steel is iron,
the weak brittle metal that was used for thousands of years.
And how do we turn a very soft, brittle metal into a strong,
sturdy metal? The element that is mixed with iron to give it strength is none
other than carbon! However, the amount of carbon that is found in steel is less
than 2%! Just that small amount of carbon turns brittle iron into sturdy steel.
There is a few problems with the addition of carbon. If you add too little
carbon, it will still behave as pure iron. If you add too much carbon, you
create what’s called pig iron. Pig iron is very soft and brittle just like pure
iron. So you need the correct amount of carbon, not too much and not too
little, to get the perfect mixture and create an incredibly strong alloy. Also
found in steel are manganese, phosphorous, sulfur, silicon and traces of
oxygen, nitrogen, and aluminum.
There was a huge problem with the production of steel: the
cost! It was an extremely expensive process to turn iron into steel and be cost
efficient at the same time. In 1855, Henry Bessemer came up with a way to
create steel at an industrial level and, of course, cheaply. He started with
pig iron, mentioned earlier, and burned off all the impurities. After burning
off the impurities, he was left with steel. This process was extremely useful
and came at a most opportune time.
Henry Bessemer
The production of steel came up huge in 1914, the start of
World War I in Europe. Steel was used to build up American infrastructure, bridges,
trains and ammunition/weapons. Steel allows us to move or hold massive amounts
of weight which was very handy in transportation, storage and building. With
the production of steel came new tools to allow us to shape steel for a
specific purpose.
This use of chemistry allowed the world to move in a whole
new direction. With the addition of a few elements, iron turned into something
completely new! This new alloy still has many uses today and can be found in
our everyday life!
