What is the crystal lattice structure of gamma iron_________________?
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Answer: B. face centred cubic
Explanation
Gamma iron, also known as austenite, possesses a face-centered cubic crystal lattice structure at elevated temperatures. This crystal configuration features iron atoms located at each corner and at the center of all six cube faces. The face-centered cubic structure allows gamma iron to dissolve significantly larger amounts of carbon than low-temperature alpha iron. Allotropy refers to the ability of iron to exist in different crystal lattice structures depending on temperature variations. Austenite is a crucial high-temperature phase in steel metallurgy that enables heat treatment and phase transformation hardening. Upon cooling below specific eutectoid temperatures, gamma iron transforms into ferrite and cementite microstructures.
Body-centered cubic crystal structures characterize low-temperature alpha iron and ferrite rather than high-temperature gamma iron. Hexagonal close-packed structures are typical of metals like titanium and magnesium, not high-temperature allotropic forms of iron. Cubic structure and orthorhombic crystal labels are overly broad or incorrect for identifying the specific face-centered cubic austenite.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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