Stability, Durability and Crystallization of Iron Phosphate Glasses Melodie Schmitt, Liying Zhang, Mark E. Schlesinger and Richard K. Brow

University of Missouri–RollaNSF DMR 0502463

Glass Preparation and Characterization

Phase Equilibria in Iron Phosphate Systems Prepared all ferric and ferrous phosphates. Characterized phase transitions by DTA and

compositional changes along Fe2O3-P2O5 liquidus surface by SEM-EDS.

Determined enthalpy change for iron reduction in FePO4 and Fe3PO7.

Analyzed decomposition of Fe3PO7 above 1100°C .

Decomposition of FePO7 quenched from 1200°C

20 30 40 50 60

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XR

D inte

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20 30 40 50 60

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BSE image Fe map

P map

Fe3PO7

Fe2O3+FePO4…

Prepared glasses with range of O/P and Fe2+/Fe3+ ratios.

Crystallization behavior (by XRD, DTA) depends on redox conditions and particle size. ‘Glass stability’ parameters will be

established in collaboration with Brazilian partners.

Melt conditions affect glass structure.

Stability, Durability and Crystallization of Iron Phosphate Glasses: Stability, Durability and Crystallization of Iron Phosphate Glasses: A CIAM CollaborationA CIAM Collaboration

NSF DMR 0502463NSF DMR 0502463

Liying Zhang (left) and Melodie Schmitt (right) are two MSE PhD candidates involved in the UMR research projects. They mentor two undergraduate research assistants.

The principal investigators for this inter-national collaboration: Dr. Mark Schlesinger (UMR), Dr. Miguel Prado (Bariloche, Argentina), Dr. Edgar Zanotto (Univ. São Carlos, Brazil) and Dr. Richard Brow (UMR).