Journal of thermal analysis

, Volume 36, Issue 7–8, pp 2593–2599 | Cite as

Studies on the thermal stability of iron chromite in air

  • Supriti Sarkar
  • J. Ghose
Article
Received:
Revised:

Abstract

Studies on the thermal stability of FeCr2O4 in air show that surface oxidation preceeds bulk oxidation. Electrical resistivity and thermoelectric power measurements show that above 47 K, Fe2+ ions are oxidised by the oxygen adsorbed on the surface and above 523K diffusion of the ions into the bulk occur. DTA and TG show that the bulk oxidation starts above 673 K and the change from the defect spinel phase to the rhombohedral phase occurs during oxidation and is not a sharp transition.

Keywords

Oxidation Iron Polymer Thermal Stability Electrical Resistivity 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Zusammenfassung

Untersuchungen der thermischen Stabilität von FeCr2O4 in Luft zeigen, daß der Masseoxidation eine Oxidation an der Oberfläche vorangeht. Messungen des elektrischen Widerstandes und der thermo-elektromotorischen Kraft zeigen, daß die Fe2+-Ionen oberhalb 47 K durch den an der Oberfläche adsorbierten Sauerstoff oxidiert werden und daß oberhalb 523 K eine Diffusion der Ionen in das Innere abläuft. DTA- und TG- Untersuchungen zufolge setzt die Masseoxidation oberhalb 673 K ein und während der Oxidation verläuft ein unscharfer Übergang von der defekten Spinellphase in die rhomboedrische Phase.

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Copyright information

© Wiley Heyden Ltd., Chichester and Akadémiai Kiadó, Budapest 1990

Authors and Affiliations

  • Supriti Sarkar
    • 1
  • J. Ghose
    • 1
  1. 1.Department of ChemistryIndian Institute of TechnologyKharagpurIndia

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