Properties of Alloys and Aluminium

Front

Explain why alloys are often stronger than their component pure metals.

Back

Alloys contain atoms of different sizes which distort the metal lattice, hindering dislocation movement and increasing strength. Alloying improves strength, hardness, and sometimes corrosion resistance.

Front

Compare the mechanical properties of a pure metal and its alloyed form.

Back

Pure metals are generally softer and more ductile. Alloys such as brass (copper + zinc) or steel (iron + carbon) have higher strength and hardness. Alloying improves strength but may reduce ductility.

Front

Why are alloys generally stronger than pure metals?

Back

They restrict dislocation movement. Alloying introduces atoms of different sizes, disrupting the regular metal lattice and restricting dislocation movement, increasing strength.

Front

Describe the advantages and disadvantages of using aluminium in the construction of transport vehicles.

Back

Advantages: Lightweight (reduces fuel consumption), corrosion resistant (no rusting), good strength-to-weight ratio.

Disadvantages: Lower tensile strength than steel, more difficult and costly to weld, can deform more easily under stress.

Front

Compare the use of aluminium alloys and ferrous metals in transport structures.

Back

Aluminium alloys are lighter and resist corrosion better than ferrous metals, making them ideal for vehicles and aircraft.

Ferrous metals, such as mild steel, are stronger and less expensive but are heavier and can rust without protection.

Front

Explain why aluminium alloys are often preferred over pure aluminium in structural applications.

Back

Pure aluminium is soft and has low tensile strength.

Aluminium alloys (e.g., 2024 or 7075) contain copper, magnesium, or zinc to improve strength, hardness, and formability.

Front

Identify two typical applications of aluminium alloys in aircraft and explain why they are used.

Back

Applications: fuselage skins, wing spars, seat frames.

Reasons: aluminium alloys are lightweight (improving fuel efficiency), corrosion resistant (longer service life), and have good tensile strength for structural integrity.

Front

Why is aluminium used in the manufacture of aircraft fuselages?

Back

It has a high strength-to-weight ratio, making it ideal for aerospace structures where weight savings are critical.

Front

Explain why engineers select non-ferrous metals for applications in the civil structures or transport industries.

Back

Engineers select non-ferrous metals such as aluminium, copper, and titanium due to their distinct properties:

• Aluminium is lightweight, corrosion-resistant, and easy to machine;

• Copper has excellent electrical and thermal conductivity;

• Titanium offers a high strength-to-weight ratio and corrosion resistance.

Front

Explain how the properties of aluminium make it suitable for its application in aircraft fuselages.

Back

Aluminium is a commonly used non-ferrous metal in aircraft fuselages due to its low density for fuel efficiency, high corrosion resistance without needing protective coatings, and good formability for complex aerodynamic shapes.