Tensile test and ductility comparison: If a specimen of material A shows 60% reduction in area at fracture and an identical specimen of material B shows 40% reduction in area, which material is more ductile?

Introduction / Context:
Ductility in a tensile test is commonly judged by the percentage reduction in area at fracture and/or percentage elongation. A higher percentage reduction in area indicates that the material can undergo more plastic deformation before failure, hence it is more ductile.

Given Data / Assumptions:

• Specimens of equal initial dimensions are tested in tension.
• Material A: reduction in area = 60%.
• Material B: reduction in area = 40%.
• Standard tensile test conditions and accurate measurements are assumed.

Concept / Approach:
Percentage reduction in area is defined as ((A0 − Af) / A0) * 100%, where A0 is original cross-sectional area and Af is area at the fracture section. Larger values imply greater necking and plastic flow ability, which correspond to higher ductility.

Step-by-Step Solution:

Verification / Alternative check:
One may also check percentage elongation. Typically, a material with higher % reduction in area also shows higher % elongation, reaffirming the same conclusion about ductility ranking.

Why Other Options Are Wrong:

• Material B more ductile: contradicts 40% vs 60% comparison.
• Equal ductility: data clearly differ.
• “A is brittle and B is ductile”: opposite of the evidence.
• “Neither material is ductile”: reduction in area values indicate plasticity in both.

Common Pitfalls:
Confusing strength with ductility; using ultimate tensile strength alone to judge ductility; ignoring measurement consistency in necked area readings.

Final Answer:
Material A is more ductile than material B