Structural and magnetic properties of a mechanochemically activated Ti-Fe{sub 2}O{sub 3} solid mixture

Journal Article · Wed Dec 15 00:00:00 EST 2010 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2010.08.003· OSTI ID:22209968

Cristobal, A. A. ^[1]; Ramos, C. P. ^[2]; Bercoff, P. G. ^[3]; Conconi, S.; Aglietti, E. F. ^[4]; Lopez, J.M. Porto ^[1]

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1. Instituto de Investigaciones en Ciencia y Tecnologia de Materiales (INTEMA), CONICET-UNMdP, J.B. Justo 4302 - B7608FDQ, Mar del Plata (Argentina)
2. Centro Atomico Constituyentes (CAC), CNEA, Av. Gral. Paz 1499 (1650), San Martin (Argentina)
3. Facultad de Matematica, Astronomia y Fisica (FaMAF), Universidad Nacional de Cordoba, Medina Allende s/n, Ciudad Universitaria, (5000) Cordoba (Argentina)
4. Centro de Tecnologia de Recursos Minerales y Ceramica (CETMIC), CONICET - CIC, Camino, P. Centenario y 506 - B1897ZCA, M.B. Gonnet (Argentina)

The mechanochemical effects on the reactivity and properties of a titanium/hematite powder mixture with molar ratio of 1/2 are investigated. Crystalline-phase structure, composition, hyperfine and magnetic behaviors were analyzed as a function of activation time by means of X-ray diffraction, scanning electron microscopy, Moessbauer spectroscopy and vibrating sample magnetometry. The results showed that at relatively short activation times metallic Ti reduces part of the ferric ions, yielding a complex product formed mainly by a mix of two solid solutions Fe{sub 3-x}Ti{sub x}O{sub 4} (titanomagnetites), both with very different x values (0 < x < 1). Also metallic iron and superparamagnetic hematite particles were detected by Moessbauer spectroscopy. As the mechanical treatment extends the composition of the reactive mixture changes, prevailing in the end the solid solution with higher x value. In contrast, when these activated samples are thermally treated the fraction of the solid solution which is richer in Ti diminishes. This fact produces a significant variation of the saturation magnetization of the obtained material.

• OSTI ID: 22209968
• Journal Information: Materials Research Bulletin, Vol. 45, Issue 12; Other Information: Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
FERRITES
HEMATITE
IRON OXIDES
MAGNETIC PROPERTIES
MAGNETIZATION
MOESSBAUER EFFECT
POWDERS
SATURATION
SCANNING ELECTRON MICROSCOPY
SOLID SOLUTIONS
SOLIDS
SUPERPARAMAGNETISM
X-RAY DIFFRACTION