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 , d are the effective thickne and grain size).

Grain boundary diffusion makes a significant contribution to the total

1.	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 , d are the effective thickne and grain size).
A.	(Db* /D1*d) > 1
B.	(Db* /D1*d) < 1
C.	(Db* /D1*d) = 1
D.	(Db* /D1*d) < 0
Answer» B. (Db* /D1*d) < 1

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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 , d are the effective thickne and grain size).

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