Mechanical, Magnetic, and Microstructural Characterization of Ni0.9Co0.1Fe2O4 Produced by the Ceramic Method

Mônica Sumie Hieda, João Paulo Barros Machado, Eduardo de Oliveira Silva Júnior, Mateus Botani de Souza Dias, Cristina Bormio Nunes, Rodrigo Gabas Amaro de Lima, Antonio Carlos da Cunha Migliano, Vera Lúcia Othéro de Brito
2018 Materials Research  
Ni-Co ferrites, especially the ones with lower cobalt fractions, are candidate materials for applications in magnetomechanical sensors and electromagnetic wave absorbers. This work studied the microstructure, magnetostriction, flexural strength, and complex magnetic permeability of Ni 0.9 Co 0.1 Fe 2 O 4 , presenting data that weren't covered by previous literature on this composition. It was found that sieving the calcined powder before the forming operation increased the flexural strength of
more » ... exural strength of the ceramic. The Ni-Co ferrite had a saturation magnetostriction of 36ppm. The real part of the complex magnetic permeability varied between 2.2-2.3 in frequencies from 100MHz to 1GHz. In frequencies higher than 1GHz, µ' decreased sharply and reached 1 at 3.9GHz. It was found that the grinding media provided a small fraction of Al to the ferrite composition, which apparently affected the complex magnetic permeability of the material but the magnetostriction results were very close to Al-free Ni-Co ferrites with similar composition.
doi:10.1590/1980-5373-mr-2017-0694 fatcat:yynnk7qblze6rphmsqqlltmogy