Light Alloys- Aluminium Properties, Uses and Extraction Flashcards
The good properties of aluminium
Low density (1/3 of steel)
Highly resistant to most forms of corrosion
Superb conductor of electricity (along with other intrinsic qualities mean has replaced Cu in many electrical applications)
Non-magnetic and non-combustible (invaluable for electronics or offshore structures)
Non-toxic and impervious (good for food and packaging)
Strong and ductile (along with low density mean extensive use in transport)
Corrosion resistance of aluminium
Metal’s natural coating of Al2O3 provides highly effective barrier to the ravages of air, temperature, moisture and chemical attack making Al a useful construction material
How abundant is Al?
3rd most abundant element in earth’s crust
Atomic number and mass
13 and 26.98
Construction industry
Used for external features like roofing, doors, window frames, gutters.
Also internal features like ceilings, doors, elevators, floor furniture, partition walls, signs, Venetian blinds
Which modes of transport use Al?
High speed trains and ferries, automotive (car body), aerospace.
How does lightweighting of cars affect CO2 emissions?
For every 100kg saved on mass of car this equates to reduction of 9g of CO2 per km.
Recyclability of Al in cars
95% of end-of-life Al in cars can be recycled. EU and Japan require 95% recycling of the total material used in new cars
Secondary weight savings in Al cars
When Al extensively used, secondary weight savings can exceed 50%. These are due to allowing drivetrain, motor and chassis downsizing
How much Al do drivetrain, chassis and suspension and car body generally use?
Drivetrain (engine block, radiator…) 50%.
Chassis and suspension (wheels, steering…) 30%.
Car body (bonnet, doors, bumper…) 20%
Use in packaging
Disposable food containers, drink cans, aerosol cans
Electrical and thermal applications
Pans, motors. Most overhead transmission lines are Al
Other application of Al
Furniture, accessories, art
Where is Al often made?
Where hydroelectric power is cheap
Where does primary Al come from?
Bauxite. Then goes to alumina then Al
