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Page 1: v r-1li.mit.edu/Stuff/PM/MSE540/Solidification.pdf · Microsoft PowerPoint - Solidification.ppt Author: Ju Li Created Date: 4/16/2009 6:13:09 PM

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Page 2: v r-1li.mit.edu/Stuff/PM/MSE540/Solidification.pdf · Microsoft PowerPoint - Solidification.ppt Author: Ju Li Created Date: 4/16/2009 6:13:09 PM

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v ∝ r -1(1-r*/r)thermal

transportkinetics

thermodynamics

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Simulation of a dendrite growing from

a small seed crystal

http://www.mathematik.uni-freiburg.de/IAM/homepages/alfred/DS_DFG.html

Page 3: v r-1li.mit.edu/Stuff/PM/MSE540/Solidification.pdf · Microsoft PowerPoint - Solidification.ppt Author: Ju Li Created Date: 4/16/2009 6:13:09 PM

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5http://www.its.caltech.edu/~atomic/snowcrystals/

Snowflake growth is vapor→solid deposition, but similar to solidification

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Xsolute

liquidussolidus

Tmelt

TE

Xmax XE

β

α

X0

XαeXβ

e=kXα

e

X0

Page 4: v r-1li.mit.edu/Stuff/PM/MSE540/Solidification.pdf · Microsoft PowerPoint - Solidification.ppt Author: Ju Li Created Date: 4/16/2009 6:13:09 PM

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Last Batch of Liquid Forms Eutectic Solid (γ+β)

Comparable volume fraction of γ, β:Lamellar microstructure

Low volume fraction of β or γ:Rod-like microstructure

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Page 5: v r-1li.mit.edu/Stuff/PM/MSE540/Solidification.pdf · Microsoft PowerPoint - Solidification.ppt Author: Ju Li Created Date: 4/16/2009 6:13:09 PM

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XE

X0

Scheil-Gulliver equation

Xβ = kXα

Page 6: v r-1li.mit.edu/Stuff/PM/MSE540/Solidification.pdf · Microsoft PowerPoint - Solidification.ppt Author: Ju Li Created Date: 4/16/2009 6:13:09 PM

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Recipe for Purification – Zone Refinement

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Page 7: v r-1li.mit.edu/Stuff/PM/MSE540/Solidification.pdf · Microsoft PowerPoint - Solidification.ppt Author: Ju Li Created Date: 4/16/2009 6:13:09 PM

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Page 8: v r-1li.mit.edu/Stuff/PM/MSE540/Solidification.pdf · Microsoft PowerPoint - Solidification.ppt Author: Ju Li Created Date: 4/16/2009 6:13:09 PM

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α/β Ti-Alloy:

Formation of Sideplates

Basketweave / Widmanstättenmicrostructure

CAMM from Yunzhi Wang, Hamish Fraser, Mike Mills, OSU

Mullins-Sekerka Instability

Page 9: v r-1li.mit.edu/Stuff/PM/MSE540/Solidification.pdf · Microsoft PowerPoint - Solidification.ppt Author: Ju Li Created Date: 4/16/2009 6:13:09 PM

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