Metals, such as gold, iron, or aluminum, are found in the Earth and are among the most common elements on the planet. Metals are used for lots of different things, such as making jewelry or weapons. But metals sometimes have undesirable characteristics. Iron, for example, is strong, but it rusts easily in damp weather. Metal alloys are metals that have combined with another substance to make them better.
- Alloys are made in one of three ways: 1) by melting the substances and combining them; 2) by grinding the substances into powders and combining them with high heat and high pressure; and 3) by shooting beams of ions into a piece of metal.
- Amalgram, used for dental fillings, is made from mercury, tin, silver, zinc, and copper.
- Brass is mostly copper with zinc.
- Cast iron is a combination of iron, carbon, and silicon.
- Stainless steel is made from iron and chromium with smaller amounts of carbon, nickel, and manganese.
Solid solution: the process of making an alloy by melting the components and mixing them
Powder metallurgy: the process of making an alloy by crushing the components into powders and combining them
Ion implantation: a precise method of making alloys by firing ions into the metal
Q and A
Question: Are alloys always better than the original metal?
Answer: Alloys are made to fit a specific purpose. They may be stronger, conduct electricity better, or be more durable than the original metal, depending on what they’re needed for.
Watch a video about making alloys at the National Defense Education Program.
Head over to Chem4Kids to learn more about alloys.