14. If the overall diffusion coefficient in presence of dislocations is given as D = D...

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14. If the overall diffusion coefficient in presence of dislocations is given as D = D + g*Dp, where g is the fraction of atoms along the dislocation line, Dp is the pipe diffusion coefficient and D is the lattice diffusion coefficient, calculate the temperature at which lattice and pipe diffusion contributes equally to the overall diffusion coefficient in silver with a dislocation density equal to 107 cm2. Also indicate the temperature ranges at which pipe diffusion and at which lattice diffusion dominates. Dp = 0.1 exp (-19700/RT) cm/sec DL= 0.7 exp (-45000/RT) cm/sec Assume that dislocation core diameter is 20 and that the atoms in the dislocation core are 20% larger in the dislocation core. 14. If the overall diffusion coefficient in presence of dislocations is given as D = D + g*Dp, where g is the fraction of atoms along the dislocation line, Dp is the pipe diffusion coefficient and D is the lattice diffusion coefficient, calculate the temperature at which lattice and pipe diffusion contributes equally to the overall diffusion coefficient in silver with a dislocation density equal to 107 cm2. Also indicate the temperature ranges at which pipe diffusion and at which lattice diffusion dominates. Dp = 0.1 exp (-19700/RT) cm/sec DL= 0.7 exp (-45000/RT) cm/sec Assume that dislocation core diameter is 20 and that the atoms in the dislocation core are 20% larger in the dislocation core.