Question

The ability of materials to develop a characteristic behaviour under repeated loading is

• A. Fatigue
• B. Hardness
• C. Resilience
• D. Toughness

Hint:

Associate key loading conditions with material properties:
- Repeated/Cyclic Load $\rightarrow$ Fatigue.
- Static Indentation/Scratch $\rightarrow$ Hardness.
- Energy Absorption (Elastic) $\rightarrow$ Resilience.
- Energy Absorption (Plastic, before fracture) $\rightarrow$ Toughness.

Answer 1

The Correct Option is A

Step 1: Understanding the Question:
The question asks us to identify the material property that represents the behavior of a material when it is subjected to repeated or cyclic loading over a period of time.

Step 2: Detailed Explanation:
Each material property has a specific meaning.

• (A) Fatigue: Fatigue is the phenomenon in which a material gradually weakens and eventually fails due to repeated application of fluctuating or cyclic stresses, even when these stresses are below the ultimate strength. This directly matches the condition described in the question.

• (B) Hardness: Hardness refers to the ability of a material to resist indentation, abrasion, or scratching and is unrelated to repeated loading.

• (C) Resilience: Resilience is the capacity of a material to absorb elastic strain energy and recover its original shape after the load is removed.

• (D) Toughness: Toughness represents the total energy a material can absorb before fracturing, including both elastic and plastic deformation.

The phrase "repeated loading" is the defining characteristic of fatigue failure, making fatigue the correct material property in this case.

Step 3: Final Answer:
The characteristic behavior developed by a material under repeated loading is known as fatigue.