Category Metals

Much of the metal we use has been used before. You can use metals again and again, by melting them down and making new things from them. This is called recycling. Recycling is very important.

 

Recycling saves energy.

Taking metal from rocks in the ground is expensive and uses up lots of energy. It creates pollution when the rocks are shipped across the world in trucks and boats. Each year, we use so many aluminium cans that if you stacked them, they could reach to the Moon and back! You can make twenty recycled cans with the same energy needed to make just one new can.

 

 

 

A magnet sorts out different metals.

Machines chew up the old bits of metal in washing machines, cars and cans. The machine squeezes out small clean pieces of metal. A huge magnet separates iron and steel. Each type of metal is melted down and used again.

 

 

 

 

 

You can sort out different metals.

Some metals are magnetic. This means they will be pulled towards a magnet. Iron and steel are magnetic. Copper and brass are not. With a small magnet, try to pick up a selection of metal objects. Which ones are magnetic?

We use metals every day. Our lives would be very different without metals. Scientists are always finding amazing new ways to use metals. They look for new places to dig for metals and for new metal materials to make.

 

 

There are metals at the bottom of the sea!

It is expensive to dig deep below the sea but it may cause less pollution and damage to the area than mining on land. Some scientists are looking into ways of using tiny creatures called bacteria to collect the metals from the sea!

 

 

 

Metal blankets keep out flames.

Using aluminium and other metals in blankets keeps in heat and keeps out flames. These thermal blankets are used in space to keep astronauts warm, and here on Earth to protect climbers on cold, snowy mountains.

 

 

 

 

There are metals in space!

High above the sky, metals are found in shining stars, on other planets and in huge pieces of rock that float around in space. If humans ever build on another planet, may be they could use the supply of metal from outer space.

 

 

Metals are strong, but they can be made into many shapes. There are lots of ways to shape metal. Most metals can be bent and pulled when they are very hot. A few metals, such as copper, lead and gold, can be shaped even when they are cold.

 

 

 

 

 

Copper is pulled into thin wires.

Hot runny metal can be poured into a mould to set, like a jelly – but the cold metal will not wobble! Hot steel is squashed in huge rollers. Gold and silver can be hammered into sheets as thin as paper. Copper is stretched into thin tube shapes to be used for wires. Copper and gold do not have to be heated before they are shaped.

 

 

Continue reading “Metal Bend and stretch”

 

 

Some metals can be used on their own. Copper is used to make wires. Metals can also be mixed with other things, to make stronger or more useful metal. A mix of copper and zinc makes strong and shiny brass.

 

 

 

 

 

 

 

Bronze is a mix of copper and tin.

A metal that is used on its own is called a pure metal. A metal that is mixed with another material is called an alloy. Alloys can have special features to do special jobs. Mixing copper and tin makes bronze. This is stronger than pure tin and it doesn’t rust.

 

 

 

 

 

 

Some metals can be made very strong!

There are some alloys called super plastic alloys. These are made using a mix of aluminium and other materials. The mix is heated up to make the alloy both strong and stretchy. Super plastic alloys are useful in buildings, cars, trains and aeroplanes.

 

 

 

 

Some metals rust when they become wet.

Have you ever seen a rough, brown-red patch on a car? This is rust. Iron turns brown and rusty when it becomes wet. Some metals, such as gold, never tarnish (change colour). Special paints or coverings can stop iron cars from rusting.

 

 

 

Before we can use metal and make it into useful objects, it must be taken out of the rock. When the rocks have been dug out of the ground, they are taken to a factory. Here, the metal is taken out. This is done in different ways for different kinds of metal.

 

 

 

 

 

 

 

 

Rock can be taken to a factory by truck.

Metal ores are loaded onto trucks, ships and trains to take them from a mine to a factory. This may be in another country. At the factory, the ore goes though many processes, or changes. The metal is extracted or taken out of the rock. There are many ways to do this.

 

 

Continue reading “Rock of metal”

 

You can find some metals in rivers or buried at the bottom of the sea. Others, such as iron, are found in rocks deep under the ground. There are many ways to dig rocks out of the ground. This is called mining.

 

 

 

 

 

Have you ever seen a hole in the ground, the size of 1,000 football pitches? It may be an open cast mine, dug by machines and miners. Metals, such as copper, lie in rocks near the ground. They are dug from these open cast mines. Huge drills and blasts of explosives loosen the rocks. Special machines scoop out the rocks and load them onto trucks.

 

 

Continue reading “Mining for metals”