Question

Explain why steel is preferred to copper, brass, aluminium in heavy-duty machines and in structural designs.

Answer 1

Young's modulus of steel is 2*10 to the power11 NM ^-2 but it is less for copper brass and aluminium

Hence steel is preferred

Answer 2

first of all, see Young's modulus of steel , copper , brass and aluminium.
The Young’s modulus of steel is 2 × 10¹¹ N/m² .
Young's modulus of copper is 1.17 × 10¹¹ N/m²
Young's modulus of brass is 1 - 1.25 × 10¹¹ N/m²
Young's modulus of aluminium is 0.69 × 10¹¹ N/m²
what you observed ? values of Young's modulus in case of copper, brass and aluminum are less than Young's modulus of steel. This means , steel is more rigid than that of copper, brass and Aluminium.

Hence steel is preferred to copper, brass, Aluminium in heavy-duty machines and in structural designs