Avrami equation

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The Avrami equation describes how solids transform from one phase (state of matter) to another. It can specifically describe the kinetics of crystallisation, can be applied generally to other changes of phase in materials, like chemical reaction rates, and can even be meaningful in analyses of ecological systems. It's expressed as:

$F(t)=1-\exp\, {[-Kt^n]}$ ,

which solves for the fraction of a volume transforming from one phase to another, with t representing time. It can be rewritten:

$\ln\, {(\ln {[1-F(t)]})}=-\ln K+n\ln t$ .

The equation is also known as the Kolmogorov-Johnson-Mehl-Avrami, or KJMA, equation. The equation was popularized by Melvin Arvami in papers published in the Journal of Chemical Physics from 1939 through 1941.