1.Metals

1.Metals

1. Metals are substances from minerals wich contain one or more metalic elements, and sometimes non-metalic substances such as carbon.

2. 1.1 How meta!s are obtained

   • Metals come from mineral wich are part of rock. .Mining is carried out in surface mines if the minerals are close to the surface mines if the minerals arre close to suface or in underground mines if they are deeper under the surface.
   • In mines, the useful minerals, or ore, and the useless minerals, or gangue together and must be separated using different physical processes . The ore is taken to an ironworks and undergoes complex physical and chemical processes.
   • The metallurgy is the group of industries involved in mining and transforming metallic minerals

3. 1.2. Classifying Metals

   • Ferrous metals
     • Their main component is iron
   • Non-ferrous metals
     • Their main component is not iron

4. 1.3. Properties of metals

   • They are tough
   • They melt at high temperatures so they can also be used for welding
   • They are ductile and malleable
   • They expand when the temperature rises and contract when it cools.
   • They can be recycled and reused
   • Some are magnetic and are attracted to magnets
   • They are good electrical, thermal and acoustic conductors

5. 2. Ferrous metals

6. The steel-making process

   • Iron mineral is washed to eliminate any impurities
   • It is crushed and sieved to separate the gangue from the ore
   • The ore is mixed with coke and limestone, and then put into a blast furnace with temperatures of over 1500ºC
   • Slag is obtained. This is a by-product made up of carbon and other impurities
   • Quenching, which is cooling the metal very quickly when it is red hot
   • Tempering , where the hot metal is cooled very slowly

7. 3. Non ferrous metals

   • 3.1. Ultra-light metals
   • 3.2. Light metals

8. 3.3. Heavy metals

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