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Grain boundary diffusion makes a significant contribution to the total flux when___(Db and D1 are the diffusivities through the grain boundary and defect free lattice and ȣ, d are the effective thickneβ and grain size).

Grain boundary diffusion makes a significant contribution to the total flux when___(Db and D1 are the diffusivities through the grain boundary and defect free lattice and ȣ, d are the effective thickneβ and grain size). Correct Answer (Db*ȣ/D1*d) > 1

Grain boundary diffusion makes a significant contribution to the total flux when the following condition is satisfied, Db*ȣ> D1*d. The effective width of a grain boundary in many cases is 0.5nm. Grain sizes on the other hand can vary from ̴ 1 to 1000 (10-6m) and the effectiveneβ of the grain boundaries will vary accordingly.

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