Topic: Strength of Materials
A material has a yield strength of 300 MPa and a fracture strain of 0.2. What is the approximate toughness (assuming linear elastic behaviour)?
- A. 60 MPa
- B. 30 MPa
- C. 600 MPa
- D. 300 MPa
Answer: B. 30 MPa
Explanation: Toughness is represented by the total area under the stress-strain curve up to fracture. Assuming a simplified linear elastic behaviour (a triangular area) extending up to fracture point for approximation:
$Area = \frac{1}{2} \times stress \times strain = \frac{1}{2} \times 300~MPa \times 0.2 = 30~MPa$.