Properties of metals and alloys

• • Metallic bonds are very strong and are a result of the attraction between the positive metal ions and the negative delocalised electrons within the metal lattice structure

  
• • Most metals have high melting and boiling points 
  • There are strong electrostatic forces of attraction between the positive metal ions and the negative delocalised electrons within the metal lattice structure
  • These needs lots of energy to be broken 
• • Most metals are malleable
  • This means they can be hammered into shape
  • This is because the atoms are arranged in layers which can slide over each other when force is applied 
• An alloy is a mixture of two or more metals or metal with a non-metal such as carbon
• • Alloys often have properties that can be very different from the metals they contain
  • They can be stronger and harder
  • They are resistance to corrosion or extreme temperatures
  • These enhanced properties can make alloys more useful than pure metals
• • Alloys contain atoms of different sizes so the layers become distorted 
  • This makes it more difficult for the layers of atoms to slide over each other, so alloys are usually much harder than the pure metal