Original scientific paper

On the Temperature Corresponding to a = 0.632 in Non-isothermal JMA Kinetics

Aleksandar Bezjak
Stanislav Kurajica
Juraj Šipušić

Abstract

The expression for rate, da/dT, of the nucleation and growth (NG) process under non-isothermal
conditions, as described by the Johnson-Mehl-Avrami (JMA) kinetic model, served as the
basis for a detailed study of a class of functions F(m) = (da/dT)Tm, where m ÎÂ. Studies of
the fractional conversion, a, of the NG process at the temperature of the maximum of function
F(m), T = T(m), have shown that when reduced activation energy, x = E/RT, approaches infinity
(x®¥), fractional conversion, a, at the temperature corresponding to the maximum of
function F(m), a(m), converges to a = 0.632, for any value of m. It has been further shown
that fractional conversion, a, for the NG process is equal to a = 0.632 at the temperature corresponding
to the maximum of function F(m) = (da/dT)Tm for the particular value of parameter
m from the interval: 1 £ m £ 2.

Keywords

Arrhenius integral; fractional conversion; JMA; non-isothermal kinetic model

Hrčak ID:

12804

URI

https://hrcak.srce.hr/12804

Publication date:

11.3.2007.

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