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Alloys

• Alloys are either a mixture of different metals, or a mixture of a metal with different elements.

• Alloys are created typically by melting down the mixture of elements until they are all in liquid state, and then mixing them together. Once mixed, the mixture is cooled until it becomes solid.

Properties of Alloys

• There is a large range of properties that alloys may possess, below are a few of the most common properties that alloys may have

Alloy Examples:

• Brass → made up of a mixture of copper and zinc

• Rose Gold → made up of a mixture of pure gold and copper

• Sterling Silver → made up of a mixture of silver and copper

• Bronze → made up of a mixture of copper and tin

What Are Metal Alloys?

Alloys are mixtures of two or more elements where at least one element is a metal. The most common alloys contain transition metals. But, alloys of the alkali and alkaline earth metals do exist. They are considered solutions. The solvent is the main metal to which other elements are added. Alloys were created from the study of inorganic chemistry. Industrial alloy production is a branch of materials science called metallurgy.

Importance of Alloys

The properties of alloys are different from the individual metals used to make them. Combining the two metals create both physical and chemical changes. However, typical metal properties like hardness and conductivity are still present. The combinations of elements improve the properties of the material. Improved qualities include:

• Conductivity

• Resistance to corrosion

• Better durability

• Heat resistance

How Are Alloys Made?

The materials to make alloys are combined together at very high temperatures. They are combined in their liquid state and then cooled. In the solid state is the final alloy material. The new material cannot be physically separated and is, therefore, a homogenous mixture. Because alloys are not made of pure metals, they are often cheaper than pure materials.

Alloy Examples

Alloys are very popular and widely used. Some examples are:

• Brass - made of copper and zinc, used in plumbing and machinery

• Bronze - a combination of copper and tin, it has been used for many years for tools and other instruments.

• Steel - consists mainly of iron and carbon, but also contains other elements like cobalt or nickel. Steel has often been used to create building structures.

• Sterling silver - used in jewelry it is made from a mixture of silver and copper. The added copper helps with strength, but can become tarnished.

(Video) Alloy & their Properties | Properties of Matter | Chemistry | FuseSchool

By FuseSchool - Global Education

This video covers alloys which are combinations of metals. Alloys maintain metallic properties, but the two metals combined create a stronger material.

Metals have few valence electrons and are able to gain or lose electrons. When metals pack together they form a lattice. A single metal atom can be surrounded by up to twelve other metal atoms. However, there are various conformations of metal-metal lattices and the surrounding atom number can be less than twelve.

In the metal lattice structure, the valence electrons are able to move from one atom to another. The flow of electrons through the material makes metals good conductors of heat and electricity.

Ductility is the ability to mold and shape metals, which comes from the variation in atom structure. Metal atoms can move past each other.

In alloys more than one metal is present. The proportions within an alloy are not fixed, like in nonmetal compounds with different atoms.

An early example of an alloy is bronze. Bronze is the combination of copper with a small amount of tin. Copper on its own is soft and can dent, but when combined with tin the material is much stronger.

There are various example of alloys such as bronze, brass, carbon steel, stainless steel, aluminum alloys, amalgam, solder, and carat gold.