ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract The oxidation kinetics of CuFeO2 in the Cu-Fe-O system have been studied between 500 and 900° C in an atmosphere containing 1 vol% oxygen in a nitrogen stream using thermogravimetric analysis (TGA). It was found that addition of Fe2O3 to the CuFeO2 caused a decrease in the oxidation rate while addition of CuO caused an increase. On increasing the concentration of Fe2O3 the activation energy was found to increase from ~ 18 kcal mol−1 to ~ 45 kcal mol−1 and the exponent ‘n’ in Avrami's equationf=1-exp (−kt n) was also observed to increase, from 1.3 to 2.3. On adding CuO to the CuFeO2 in the Cu-Fe-O system the activation energy decreased from ~ 18 kcal mol−1 to ~ 8 kcal mol−1. The variation in both values indicates changes in the oxidation mechanisms. The microstructural changes associated with oxidation have been studied using optical microscopy. A model has been proposed to explain the results.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00552064
