Difficulty: Easy
Correct Answer: Yes
Explanation:
Introduction / Context:
Brittleness and ductility describe how materials behave near fracture. Understanding these differences is vital for safe design, material selection, and failure analysis under tensile loading.
Given Data / Assumptions:
Concept / Approach:
Brittle fracture occurs with minimal prior plastic flow; cracks propagate rapidly once initiated, often along cleavage planes or flaws. The stress–strain response shows a near-linear portion until catastrophic break, unlike ductile metals that display yielding and necking with noticeable elongation before fracture.
Step-by-Step Solution:
Define brittleness: low capacity for plastic deformation under tensile stress.Relate to tensile test observations: negligible uniform elongation, sudden fracture.Conclude that the statement is correct for classic brittle materials.
Verification / Alternative check:
Fractography of brittle materials reveals shiny, granular, or mirror/mist/hackle regions without ductile dimples. Engineering handbooks distinguish brittle from ductile failure modes precisely on elongation at break.
Why Other Options Are Wrong:
Common Pitfalls:
Assuming all metals are ductile; some alloys (e.g., white cast iron) behave in a brittle manner under tension.
Final Answer:
Yes
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