Question

Which of the following is/are an alloy of Aluminium?

• A. Duralumin
• B. Magnalium
• C. Alnico
• D. All of these

Answer 1

The correct option is D

All of these

Due to its low density, corrosion resistance, and lightweight, Aluminium ($Al$) is one of the most sought-after metals used to prepare alloys.

To answer this question, we must first understand the composition of the given alloys.

Explanation for correct option:

A) Duralumin: Duralumin is mainly composed of ($90\%$) Aluminium ($Al$), $4\%$ Copper ($Cu$), $0.51\%$ Magnesium ($Mg$), and less than $1\%$ Manganese ($Mn$). It is lightweight but strong and hence is used to make wires, rods, and screws for machine parts.

B) Magnalium: Magnalium is an alloy of $5\%$ Magnesium ($Mg$) and $95\%$ Aluminium ($Al$). It finds application in the manufacturing of aircraft parts due to its lightweight.

C) Alnico: As the name suggests, Alnico is an alloy made from a combination of Aluminium ($Al$), Nickel ($Ni$), Cobalt ($Co$) mainly but Iron ($Fe$) and varying levels of Copper ($Cu$), Titanium ($Ti$), and Niobium ($Nb$) are also present at times depending on the alloy grade. It is used for manufacturing engineering parts such as electric motors.

Therefore, the correct answer is (D) All of these.