Structural and magnetic behavior of Pr-substituted M-type hexagonal ferrites synthesized by sol–gel autocombustion for a variety of applications

• Published in: Journal of magnetism and magnetic materials 2015-01, Vol.374, p.187-191
• Main Authors: Abbas, Waseem, Ahmad, Ishtiaq, Kanwal, M., Murtaza, Ghulam, Ali, Ihsan, Azhar Khan, Muhammad, Akhtar, Majid Niaz, Ahmad, Mukhtar
• Format: Article
• Language: English
• Subjects: Coercive force; Diffraction; Ferrites; M-type hexaferrites; Magnetic permeability; Micrographs; Microstructure; M–H loops; Pr-substitution; Saturation (magnetic); Sol gel process; Sol–gel; Thermal properties
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2014.08.029

A series of M-type hexaferrites with chemical formula Ba0.25Sr0.75PrxFe12−xO19 (x=0.00, 0.05, 0.10, 0.15, 0.20, 0.25) were synthesized using sol–gel autocombustion method. The samples were pre-sintered at a temperature of 800°C for 3h and were finally sintered at 1200°C for 1h at the heating rate of 10°C/min. The thermal properties of the specimen have been investigated by thermogravimetric and differential thermal analyses. The structures and micrographs of the samples were systematically examined by X-ray diffraction and scanning electron microscopy, respectively. Vibrating sample magnetometer was also used in order to study the magnetic parameters of these ferrites. The hard magnetic behavior was confirmed by M–H loops for all the samples except for the sample with x=0.10 concentration which exhibits maximum saturation magnetization (Ms) and a few hundred oersteds of coercivity (Hc). Thus high Ms and low Hc cause to increase the permeability of the sample which is favorable for impedance matching in microwave absorption. •M-type ferrites Ba0.25Sr0.75PrxFe12−xO19 were synthesized using sol–gel autocombustion.•The samples were finally sintered at 1200°C for 1h at the rate of 10°C/min.•The sample with x=0.10 concentration exhibits maximum Ms and a low coercivity (Hc).•These parameters are favorable for impedance matching in microwave absorption.•Hard magnetic nature is revealed by other samples that are suitable for magnetic recording.