Solve this multiple-choice question and choose the correct option.

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Crystal structure of γ-iron (austenite) Identify the space lattice of gamma iron (the high-temperature phase of iron known as austenite). Choose the correct option.

Difficulty: Easy

Face centred cubic (FCC) space lattice
Body centred cubic (BCC) space lattice
Close-packed hexagonal (HCP) space lattice
None of these

Correct Answer: Face centred cubic (FCC) space lattice

Explanation:

ConceptGamma iron (austenite) has a face centred cubic (FCC) structure. Alpha iron (ferrite) is BCC at room temperature, while HCP does not occur in pure iron under normal conditions.

Final AnswerFace centred cubic (FCC) space lattice

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