Metals Flashcards
What is an alloy?
2 or more metals combined to combine properties
What are the properties and uses of cast iron?
- strong
- brittle
- car brake disks
- vices
What is mild steel?
Iron and carbon
What are the properties and uses of mild steel?
- strong
- cheap
- rusts easily
- screws
- nails
What is stainless steel?
Iron + carbon + chromium + nickel
What are the properties and uses of stainless steel?
- hard
- doesn’t rust
- expensive
- surgical equipment
- cutlery
What are the properties and uses of zinc?
- weak
- resists corrosion
•coating metal such as steel
What are the properties and uses of copper?
- soft
- malleable
- conductive
- ductile
- water pipes
- pans
What are the properties and uses of brass?
- strong
- resists corrosion
- malleable
- ductile
- conductive
- door handles
- electrical parts
What are the properties and uses of silver?
- soft
- malleable
- ductile
- conductive
- expensive
- jewellery
- expensive cutlery
What is pewter?
Tin + copper + antimony
What are the properties and uses of pewter?
- soft
- cheaper than silver
- jewellery
- ornaments
What are the different forms metal can come in?
- sheet
- strips
- different shaped rods / bars (circles / squares etc)
- pipes / tubes
- angle shaped
- u shaped channel
- I shaped girder
Why is it good that manufacturers can get their metal in different forms?
So that they can get roughly the size that they need minimising waste and costs
Where is metal extracted from?
Metal ore
What happens to metal ore to extract the metal?
It is crushed and heated to melt it in a blast furnace and is the refined to remove impurities
The molten metal is cast (poured into a mould) and can be run through rollers to shape it
What can beat treatments do to metals?
Change their properties
What is annealing?
The metal is heated and left to cool slowly
What properties does annealing add?
- softer
- more ductile
- less brittle
What is hardening?
Heating a metal until it is red hot and then plunging it into cold water or oil
What properties does hardening add?
- harder
* brittleness
What is often done after hardening to reduce brittleness?
Tempering
What is tempering?
Steel:
Gently heated as it gets hotter it’s colour changes, the colour tells you how tough it has become
What is the colour for the weakest toughness?
Pales straw
