Lecture

Diffusion Mechanisms: Simple vs Interstitial

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Description

This lecture covers the mechanisms of diffusion in alloys, focusing on simple and interstitial exchanges. It explains the gap mechanism, where the number of gaps is conserved, and the correlation factor and number of jumps play a crucial role. The lecture also delves into the interstitial mechanism, discussing the position of interstitial atoms before and after diffusion, as well as direct and indirect mechanisms. Various types of exchanges, such as simple, cyclical, and incomplete, are explored, along with the impact of correlation effects on diffusion calculations. The presentation concludes by comparing cubic and non-cubic structures in diffusion mechanisms.

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The phrase "correlation does not imply causation" refers to the inability to legitimately deduce a cause-and-effect relationship between two events or variables solely on the basis of an observed association or correlation between them. The idea that "correlation implies causation" is an example of a questionable-cause logical fallacy, in which two events occurring together are taken to have established a cause-and-effect relationship. This fallacy is also known by the Latin phrase cum hoc ergo propter hoc ('with this, therefore because of this').

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