Role of Defects in Solid State Diffusion Mechanisms

1V - Role of Defects in Solid State Diffusion Mechanisms 

To this point, we have examined diffusion growth in terms of nucleation and embryo formation. Let us now scrutinize the actual species which diffuse. 

WE WILL FIND THAT ALL DIFFUSION MOTION OCCUI BY DEFECT MOVEMENT IN THE LATTICE.  

Self diffusion can occur by at least two mechanisms, vacancy and interstitial. Both are hopping motions, as described above. Actually, we must account for all types of defects, including charged species (see 

To do this, let us reconsider the tarnishing reaction (Section D-I), with the general reaction  

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