Meta Material types

Everything we make is made up of one or more materials. Different materials have different properties. Because of these different properties, they can be used to make many kinds of objects. Materials can be soft or hard. They can be flexible or stiff. They can be delicate or very strong. You can distinguish the following meta material types:

Metals

Metals are some of the most important materials used in manufacturing and building. Some examples of metals are iron, aluminum, copper, zinc, tin, and lead. Many metals we use today are alloys. Alloys are made by combining two or more metals. They can also combine a metal with a nonmetal material. Alloys are made to give the metal new characteristics. Things like increased hardness or strength. For example, steel is an alloy of iron that contains a small amount of carbon.

Many metals are likely to corrode. Corrosion is a chemical reaction where metal reacts with oxygen. Sometimes this is good because it strengthens the metal. But when iron or steel react with oxygen, rust is created. Corrosion can eventually make metal break down entirely into rust.

Plastics

Plastics come in many different forms. They are used to make a wide variety of products. Plastic molecules are made up of long chains. These molecules are called polymers. Most plastics are either thermoplastics or thermoset plastics. Thermoplastics are heated and then moulded into shape. They can be reheated later and reshaped. Most plastic bottles are thermoplastic. Thermoset plastics can only be heated and shaped once. Thermoset plastics are used to make things like electrical insulation, dinner plates and automobile parts. Plastics can take a very long time to break down. Plastic bottles take about 450 years to break down. Plastic shopping bags can take as long as 10,000 years! This is why it is important to recycle plastics. Thermoplastics are recyclable, but thermoset plastics are not. When possible, it’s better to choose thermoplastics over thermoset plastics so the plastic can be given a new life after use.

Wood

Wood can be classified as either hardwood or softwood.

Hardwood comes from deciduous trees. These are trees that lose their leaves in the fall. Hardwood is usually used to make furniture and in construction projects that need to last for a long time. Examples of hardwoods are oak, maple, and walnut.

Softwood comes from coniferous trees. Coniferous, or evergreen trees, keep their needles all year round. Most timber, or wood that is prepared for construction, is made from softwood trees. Softwood is usually used in parts of buildings, like windows and doors. It is also used in some kinds of furniture. Examples of softwoods are pine, fir, and spruce.

Ceramics

Ceramics are often defined by what they’re not. They are nonmetallic and inorganic solids. This means they aren’t made of metal, wood, plastics, or rubber. They are made by baking clay, sand, and other natural materials at very high temperatures.

A few examples of ceramics are bricks, tiles, and concrete. Ceramic materials are used to make everything from the homes we live in to the pots we cook food in to dental implants for our teeth. It is even used to make the insulating tiles on space shuttles! Glass (see below) is also a ceramic.

Glass

Glass is one of the most versatile materials created by humans. Glass is made mostly of sand, which is made up of silicon dioxide. When sand is heated to a very high temperature (about 1700°C) it becomes a liquid. When it cools again, it undergoes a complete transformation and becomes a clear solid.

The glass we are most familiar with today is called soda-lime-silica-glass. It is made mostly of sand, but some other ingredients as well. Soda ash, which is made up of sodium carbonate, reduces the sand’s melting point. This means it doesn’t have to be heated to as high a temperature before it turns into a liquid. But soda ash also makes the glass water-soluble. This means it can dissolve in water! Limestone, or calcium carbonate, is added to stop this from happening.