The diffusion through the lattice can be ignored under certain circumstances. Which among the following condition should be satisfied for the same if the diffusivity through a defect free lattice is given as 2.5 mm2/sec and the grain size is given as 5mm? (Consider the diffusivity through the grain boundary as 2mm2/sec)

When the effective thickness of grain boundary is 6.25mmb) When the effective thickness of grain boundary is 1000mmc) When the effective thickness of grain boundary is 0.001mm

When the effective thickness of grain boundary is 6.25mm

When the effective thickness of grain boundary is 1000mm

When the effective thickness of grain boundary is 10mm

The diffusion through the lattice can be ignored under certain circum

1.	The diffusion through the lattice can be ignored under certain circumstances. Which among the following condition should be satisfied for the same if the diffusivity through a defect free lattice is given as 2.5 mm2/sec and the grain size is given as 5mm? (Consider the diffusivity through the grain boundary as 2mm2/sec)
A.	When the effective thickness of grain boundary is 6.25mm
B.	When the effective thickness of grain boundary is 1000mm
C.	When the effective thickness of grain boundary is 6.25mmb) When the effective thickness of grain boundary is 1000mmc) When the effective thickness of grain boundary is 0.001mm
D.	When the effective thickness of grain boundary is 10mm
Answer» C. When the effective thickness of grain boundary is 6.25mmb) When the effective thickness of grain boundary is 1000mmc) When the effective thickness of grain boundary is 0.001mm

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