Química Nova (Jan 2007)

Detailed crystallization study of co-precipitated Y1.47Gd1.53Fe5O12 and relevant magnetic properties

  • Rogério Arving Serra,
  • Tsuneharu Ogasawara,
  • Angélica Soares Ogasawara

DOI
https://doi.org/10.1590/S0100-40422007000700009
Journal volume & issue
Vol. 30, no. 7
pp. 1545 – 1549

Abstract

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The crystallization process of co-precipitated Y1.5Gd1.5Fe5O12 powder heated up to 1000 ºC at rate of 5 °C min-1 was investigated. Above 810 ºC crystalline Y1.47Gd1.53Fe5O12 was obtained with a lattice parameter of 12.41 Å and a theoretical density of 5.84 g cm-3. Dry pressed rings were sintered at 1270 and 1320 ºC, increasing the grain-size from 3.1 to 6.5 µm, the theoretical density by 87.6 to 95.3% and decreasing Hc from 2.9725 to 1.4005 Oe. Additionally, Hc increased when the frequency of the hysteresis graph varied from 60 Hz to 10 kHz, the curie temperature was 282.4 ºC and Ms equalled 9.25 emu g-1 (0.17 kG) agreeing well with the Bs-value of the hysteresis graph and literature values.

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