Non-isothermal crystallization kinetics of metal glasses: simultaneous determination of both the activation energy and the exponent n of the JMA kinetic law

✍ Scribed by J.M. Criado; A. Ortega

• Publisher: Elsevier Science
• Year: 1987
• Weight: 578 KB
• Volume: 35
• Category: Article
• ISSN: 0001-6160
• DOI: 10.1016/0001-6160(87)90117-9

✦ Synopsis

It has been demonstrated that the activation energy of a solid state transformation fitting a Johnson-Melh-Avrami (JMA) kinetic can be determinated from the Kissinger's method, even if E/RT is smaller than 5. Moreover by combining this method with the kinetic analysis of a single (da/dr)-Ttraces both the activation energy and the exponent n can be simultaneously determined. On the other hand the influence of both the kinetic law obeyed by the reaction and the values of E/RT on the error of the activation energy determined from the Kissinger's method has been analyzed. It has been shown that provided that n is higher than 1, the error is lower than 5% for E/RT 25.

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