| Autor: |
Mukhtar Ahmad, M. Kriegisch, Ihsan Ali, R. Grössinger, Frank Kubel, M.U. Rana |
| Rok vydání: |
2013 |
| Předmět: |
|
| Zdroj: |
Journal of Alloys and Compounds. 579:57-64 |
| ISSN: |
0925-8388 |
| Popis: |
Divalent (Me) ions substituted W-type hexagonal ferrites with chemical formula Ba0.5Sr0.5Co2−xMexFe16O27 (x = 0, 0.5 and Me = Mn, Mg, Zn, and Ni) were prepared by sol–gel autocombustion method at 1300 °C for 5 h. Thermal and IR spectral studies were carried out by means of differential thermal/thermogravimetric analysis and Fourier transform infrared spectroscopy respectively. The microstructure was investigated by using the powder X-ray diffractometer and the field emission gun scanning electron microscope. The results showed that divalent ions substituted W-type hexagonal ferrites were single phase and appeared as hexagonal platelet-like shape which is better shape for microwave absorption. M–H loops of a selected sample were measured up to maximum applied field of 9T in a temperature range of 4.2–400 K. The values of saturation magnetization were calculated by the law of approach to saturation. The room temperature value of coercivity is found to be a few oersteds which is favorable for EM materials. Based on the results of electromagnetic parameters, reflection losses were calculated which are found to depend on the thickness of the absorber. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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