Question:
Pearlite microstructure in an eutectoid steel consists of alternating layers of two phases, namely \( \alpha \) ferrite and
Pearlite microstructure in an eutectoid steel consists of alternating layers of two phases, namely \( \alpha \) ferrite and
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Pearlite microstructure forms when eutectoid steel cools and consists of alternating layers of ferrite and cementite.
Updated On: Dec 26, 2025
- Martensite
- Austenite
- Cementite
- Bainite
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The Correct Option is C
Solution and Explanation
In the context of eutectoid steel, the Pearlite microstructure consists of alternating layers of two phases: \( \alpha \) ferrite and cementite.
- Ferrite (\( \alpha \)) is a soft and ductile phase of iron with a body-centered cubic (BCC) structure.
- Cementite (Fe₃C) is a hard and brittle iron-carbon compound with a orthorhombic crystal structure.
When eutectoid steel (which has 0.8% carbon content) is cooled slowly, it transforms from austenite (gamma phase) into pearlite at the eutectoid composition. This transformation occurs at the eutectoid temperature of 727°C. Thus, pearlite consists of alternating layers of ferrite and cementite, not any other phases like martensite, bainite, or austenite. Therefore, the correct answer is (C).
- Ferrite (\( \alpha \)) is a soft and ductile phase of iron with a body-centered cubic (BCC) structure.
- Cementite (Fe₃C) is a hard and brittle iron-carbon compound with a orthorhombic crystal structure.
When eutectoid steel (which has 0.8% carbon content) is cooled slowly, it transforms from austenite (gamma phase) into pearlite at the eutectoid composition. This transformation occurs at the eutectoid temperature of 727°C. Thus, pearlite consists of alternating layers of ferrite and cementite, not any other phases like martensite, bainite, or austenite. Therefore, the correct answer is (C).
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