Question

Which material typically shows no yield point in its stress-strain diagram?

• A. Mild steel
• B. Cast iron
• C. Annealed copper
• D. High carbon steel

Hint:

Cast iron is brittle and typically fractures without a distinct yield point, unlike ductile materials like mild steel and copper.

Answer 1

The Correct Option is B

In a stress-strain diagram, the yield point is where the material transitions from elastic deformation to plastic deformation. Some materials, like mild steel, exhibit a clear yield point. However, cast iron is a material that typically does not have a distinct yield point. Instead, its stress-strain curve exhibits a sudden fracture or brittle failure without the obvious transition seen in materials like mild steel or copper.
- Mild steel: This material has a clear yield point where plastic deformation starts, typically seen as a sharp point in the stress-strain curve.
- Cast iron: This material is brittle and does not show a clear yield point on the stress-strain curve, as it fractures suddenly.
- Annealed copper: Annealed copper behaves similarly to mild steel in that it has a clear yield point.
- High carbon steel: High carbon steel has a clear yield point and shows typical ductility, unlike cast iron.
Thus, cast iron is the correct answer as it typically shows no yield point in its stress-strain diagram.