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The relative magnitudes of Db*ȣ and D1*d are most sensitive to_______(Where Db and D1 are the diffusivities through the grain boundary and defect free lattice and ȣ, d are the effective thickness and grain size)

The relative magnitudes of Db*ȣ and D1*d are most sensitive to_______(Where Db and D1 are the diffusivities through the grain boundary and defect free lattice and ȣ, d are the effective thickness and grain size) Correct Answer Temperature

The relative magnitudes of Db*ȣ and D1*d are most sensitive to temperature. Note that although Db > Dȣ, at all temperatures, the difference increases as temperature decreases. This is because the activation energy for diffusion along grain boundaries (Qb) is lower than that for lattice diffusion (Q1).

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