Part IB

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Part IB Materials Science and Metallurgy Course
A Metals Alloys
Professor Harry Bhadeshia
Lecture 10 Iron Alloys
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body-centred cubic (ferrite)
cubic close-packed (austenite)
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DISPLACIVE
RECONSTRUCTIVE
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Carbon in octahedral interstices in austenite
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Carbon in irregular octahedral interstices in
ferrite
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Chatterjee Bhadeshia, 2006
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Yamasaki Bhadeshia, 2004
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20 µm
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20 µm
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kilocycles to Crack Initiation
Yates, Jerath
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Yates, Jerath
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Carbon supersaturated plate
Carbon diffusion into
Carbon diffusion into
austenite and carbide
austenite
precipitation in ferrite
Carbide precipitation
from austenite
LOWER BAINITE
UPPER BAINITE
(Low Temperature)
(High Temperature)
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g
g
a
a
a
Mateo, 2002
200 Å
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Cambridge University / Science Musuem, London
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