Question

To design the body of an aircraft, aluminium alloys are used. Give reasons.

Answer 1

Hint:The aircraft bodies should be made up of a substance that is light-weight and it is still strong so that the weight remains light while the planes are in air.

Complete step by step answer:
Aluminium is a light-weight metal that does not get rusted. When aluminium reacts with oxygen and water, a coating of aluminium oxide or aluminium hydroxide is formed on the surface and the rest of the aluminium remains in its pure form beneath the surface. There are different alloys of aluminium, and among them Duralumin is used to make aircraft bodies. The reasons for the choice being:
-Duralumin has a composition of aluminium, copper, and magnesium which makes it have high tensile strength.
-It has temperature resistance and can sustain high temperatures
-It does not get corroded easily.
-For these, aluminium alloys are used to make aircraft bodies.

Note:
The composition of duralumin is $90\% $ aluminium, $4\% $ copper, $1\% $ magnesium, and $0.5 - 1\% $ manganese.Along with aircraft bodies, duralumin is also used to make armour used in the defence industry and also in ship-buildings.The typical strength of duralumin is 450 Mpa and is much higher than that of aluminium.
The electrical and heat conducting properties of duralumin are less than that of aluminium but more than that of steel.A special laminated form of Duralumin, called “alclad” is used in the aircraft industry as duralumin sometimes tends to lose strength during welding.