Abstract
Four types of phase transformation that involve the conversion of crystalline phases into more disordered forms are reviewed: melting, disordering of superlattices, amorphization by diffusion between crystalline phases, and irradation amorphization. In the review emphasis is placed on evidence for the heterogeneous nucleation of the product phases; in this connection, the role of surfaces, antiphase domain boundaries, dislocations, vacancies, and grain boundaries is specifically discussed. All of these features have been either observed, or hypothesized, to play a role as heterogeneous nucleation sites in one or more of the four transformations. An attempt is made to draw parallels between nucleation mechanisms in the various processes.
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References
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Cahn, R.W., Johnson, W.L. Review: The nucleation of disorder. Journal of Materials Research 1, 724–732 (1986). https://doi.org/10.1557/JMR.1986.0724
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DOI: https://doi.org/10.1557/JMR.1986.0724