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).

> 1b) (Db*ȣ/D1*d) < 1c) (Db*ȣ/D1*d) = 1d) (Db*ȣ/D1*d) < 0

.a) (Db*ȣ/D1*d) > 1b) (Db*ȣ/D1*d) < 1c) (Db*ȣ/D1*d) = 1d) (Db*ȣ/D1*d) < 0

Grain boundary diffusion makes a significant contribution to the tota

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 ȣ, d are the effective thickneβ and grain size).
A.	(Dbȣ/D1d) > 1
B.	(Dbȣ/D1d) < 1
C.	(Dbȣ/D1d) = 1d) (Dbȣ/D1
D.	> 1b) (Dbȣ/D1d) < 1c) (Dbȣ/D1d) = 1d) (Dbȣ/D1d) < 0
E.	.a) (Dbȣ/D1d) > 1b) (Dbȣ/D1d) < 1c) (Dbȣ/D1d) = 1d) (Dbȣ/D1d) < 0
Answer» B. (Dbȣ/D1d) < 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 ȣ, d are the effective thickneβ and grain size).

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