6533b861fe1ef96bd12c461f
RESEARCH PRODUCT
Effect of the preparation method and grinding time of some mixed valency ferrite spinels on their cationic distribution and thermal stability toward oxygen
P. PerriatB. GillotBruno Domenichinisubject
Materials scienceInorganic chemistrySpinelValencyGeneral Chemistryengineering.materialCondensed Matter PhysicsGrindingThermogravimetryLattice constantPhase (matter)engineeringFerrite (magnet)General Materials ScienceThermal stabilitydescription
Abstract The reactivity in oxygen of several mixed valency ferrite spinels, namely Fe3O4, FeCr2O4, Fe3 − xTixO4 and Fe3 − xMoxO4 was investigated by derivative thermogravimetry (DTG) analysis as a function of the conditions of preparation and grinding. For all these compounds, low temperature preparation or prolonged grinding time enables small particles ( 0.5 μm), it was observed that oxidation was starting at higher temperature and that the defect spinel phases could not be retained during oxidation. This behaviour was attributed to the presence of stresses induced by the lattice parameter gradient and promoting the formation of nuclei of the α-rhombohedral phase from the superficial γ-defect phase.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1996-04-01 |