Abstract
Changes in the structure of metals and their relation to physical and mechanical properties are the primary interest of the physical metallurgist. Since most changes in structure occur by diffusion, any real understanding of phase changes, homogenization, spheroidization, etc., must be based on a knowledge of diffusion. These kinetic processes can be treated by assuming that the metal is a continuum, that is, by ignoring the atomic structure of the solid. The problem then becomes one of obtaining and solving an appropriate differential equation. In this first chapter the basic differential equations for diffusion are given, along with their solutions for the simpler boundary conditions. The diffusion coefficient is also defined, and its experimental determination is discussed.
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Notes
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Shewmon, P. (2016). Diffusion Equations. In: Diffusion in Solids. Springer, Cham. https://doi.org/10.1007/978-3-319-48206-4_1
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DOI: https://doi.org/10.1007/978-3-319-48206-4_1
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-48564-5
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