http://cml.postech.ac.kr/

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http//cml.postech.ac.kr/
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1 µm
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Surface 1
Surface 2
50 µm
Srinivasan Wayman, 1968
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s
d
c
r
1
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50 µm
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Bhadeshia and Waugh, 1981
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Takahashi and Bhadeshia
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Fe-0.4C wt
Decarburisation time / s
Temperature / C
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Temperature
Ae3'
T'
o
x
Carbon in austenite
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TRIP-assisted steel Fe-0.29C-1.41Si-1.42Mn wt
(Jacques, 2001)
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Growth is diffusionless.
Strain energy must be accounted for.
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Takahashi and Bhadeshia
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Oka and Okamoto
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Ohmori and Honeycombe
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Summary
The mechanism of transformation is
displacive. Transformation temperature higher
than martensite. Bainite grows without
diffusion. But carbon then escapes into the
residual austenite. Shape deformation plastically
accommodated. Sub-unit mechanism of growth
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Think of bainite as martensite which tempers
during transformation
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DISPLACIVE
RECONSTRUCTIVE
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Summary
Mechanism of transformation is displacive but
carbon must partition during growth. Pairs of
plates grow together to minimise strain.