METALS AND THEIR PROPERTIES Flashcards
Name 7 common metals
Steel Stainless steel Iron Aluminium Brass Copper Bronze ASS BIB C
Where do metals come from? 5 points
Part of earth’s crust in the form of METAL ORE
Metal ore is mined and washed to remove other minerals
It is heated in a furnace and the pure metal ore is run off
This is known as SMELTING
Iron ore is the basis for most steels
What are the 2 main categories of metals?
Ferrous and non-ferrous
Give 3 points about FERROUS METALS
Contain iron
Will corrode unless protected
Attracted by a magnet
Give 2 points about NON-FERROUS METALS
Don’t contain iron
Aluminium, copper, time and lead we all non-ferrous metals
Pure Metals - 3 points
- They are metals in their basic form
- Aluminium, gold, copper, zinc, tin and lead are all pure metals CAT TGZ
- Aluminium is the most abundant of the pure metals but it has to go through some refining process to turn it into a usable material
Alloys - 4 points
- A mixture of 2 or more metals
- Brass is an alloy of 65% copper and 35% zinc
- High tensile steel is an alloy of low carbon steels and nickel
- Steel is an alloy of steel, chromium, nickel and magnesium
Name the three methods of joining metals
- Riveting
- MIG Welding
- Nuts, bolts and washers
Metals can be joined temporarily or permanently
Name 4 methods of finishing
- Painting
- Lacquering
- Plastic coating
- Enamelling
Paint - 3 points
- Surface must be smooth and degreased
- Primer required
- Hammerite is a good one-coat metal paint
Plastic coating - 3 points
- Suitable for most metals
- Object is heated and dipped in a tank of powder paint
- Object is returned to over to ensue a smooth, glossy finish
Lacquering - 3 points
- Helps to prevent corrosion after polishing
- A layer of cellulose or varnish is applied
- Often used on jewellery
Enamelling - 2 points
- Powdered glass is melted onto the metal surface
2. Provides a hard (but brittle) finish with different colours and textures
