Home > Educational Material > Learning Resources > Chemistry - Alloys

Chemistry - Alloys

An alloy is any mixture of two or more metals, or a metal and another substance.

Alloys are made because they combine the properties, such as, lightness or strength, of the different metals which make them up.

Here are some examples of alloys:

Stainless steel is an alloy of, nickel and chromium

A ships propeller is made of, bronze, an alloy of copper and tin

 

Adding strength...

In pure metals the atoms are arranged tightly in rows. The rows are able to slide over one other, which makes the metal soft. Sudden pressure can cause cracks to form across the rows making the pure metal brittle.

 

Pure Metal Structure

 

 

When another metal is added, its atoms help strengthens the first metal. It does this by holding the parts of metal together, stopping the rows from sliding over one another.

 

 

A Metal Alloy Structure

 

Properties of alloys...

An alloy’s properties depend on exactly what it is made of. Steel for example, which is an alloy of iron and carbon, combines strength with ease of use. This means that it can easily be worked into different shapes. It can also be melted without releasing poisonous fumes.

Steel’s hard-wearing properties are increased by adding manganese. Steel-manganese alloys are mostly used for industrial cutting equipment.

Some pure metals are good at resistant corrosion so they are ideal for use outside. However they are relatively expensive

Strong, light alloys...

Like steel and brass, alloys of aluminium and magnesium, are strong and corrosion resistant. They are also much lighter, they are used for aircraft and bridge frames.

Metallurgists (people who study metals) have discovered that metals are often strongest if they are alloyed with only very small amounts of other substances. This has made it possible to create alloys that are very strong but still light.

 

Super alloys...

The elements, nickel, cobalt and iron have all been used as the main ingredient in super alloys.

Super alloys are not only extremely strong, but they also retain their strength even when exposed to high temperatures for long periods of time. They are used in jet and rocket engines.

Word Document

Educational Material

Rss Feed Available RSS Our Blog Feed

Get Adobe Reader Adobe .PDF

 

Help us keep it free by donating.

LiveBinder It