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| Diffusion | ||||||||||||||||
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The
temperature dependent Diffusion Coefficient: D(T)
= D0exp (-Q/kT) m2 sec-1
where Q = "Energy" of diffusion, D0 is the temperature independent
diffusion coefficient, and T the diffusion temperature in Kelvins.
· Plotting Ln D(T) v. (103/ T) gives a straight line the slope of which yields Q · The jumps in the curves for Iron indicate that D(T) also depends on the crystal structure, being smaller in the close packed fcc structure than in the more open bcc crystal. |
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| From: Askeland, "The Science of Engineering Materials," PWS (1994) | ||||||||||||||||