Phase distribution and magnetic properties of hard/soft ferrite nanocomposites prepared through mechanical alloying and physical mixing method

Nanocomposite magnet consisting of hard and soft magnetic phases has attracted many attentions from the researcher in recent years. The exchange coupling between hard and soft phase can combine the high coercivity of the hard phase and the high magnetization of soft phase to produce a magnet with...

Full description

Saved in:
Bibliographic Details
Main Author: Ahmad, Aisyah Radhiah
Format: Thesis
Language:English
Published: 2019
Subjects:
Online Access:http://psasir.upm.edu.my/id/eprint/90029/1/FS%202019%2082%20ir.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
id my-upm-ir.90029
record_format uketd_dc
spelling my-upm-ir.900292021-12-03T01:48:46Z Phase distribution and magnetic properties of hard/soft ferrite nanocomposites prepared through mechanical alloying and physical mixing method 2019-03 Ahmad, Aisyah Radhiah Nanocomposite magnet consisting of hard and soft magnetic phases has attracted many attentions from the researcher in recent years. The exchange coupling between hard and soft phase can combine the high coercivity of the hard phase and the high magnetization of soft phase to produce a magnet with high energy product. The mechanical alloying and physical mixing method are chosen to produce the nanocomposite. The hard phase, SrFe12O19 and soft phase, Ni0.5Zn0.5Fe2O4 were mixed to become nanocomposite SrFe12O19/Ni0.5Zn0.5Fe2O4. The effect of phase distribution in the nanocomposite is studied by varying the amount of soft ferrite. While the amount of hard ferrite is kept constant. The novelty of this research lies in the different phase distribution between hard and soft phases in the nanocomposite, which gives more understanding of the effect of phase distribution on the exchange coupling. The characterizations of the samples are carried out using Thermogravimetric Analysis (TGA), X-ray Diffraction (XRD), Vibrating Sample Magnetometer (VSM), Electron Paramagnetic Resonance (EPR) and microstructure analysis using Transmission Electron Microscope (TEM) and Field Emission Scanning Electron Microscope (FESEM). The XRD results on the nanocomposites shown that both hard phase, SrFe12O19 and soft phase, Ni0.5Zn0.5Fe2O4 are present in the samples producing the SrFe12O19/Ni0.5Zn0.5Fe2O4 nanocomposite. From the mechanical alloying method, the nanocomposites with 10-20 wt.% of soft phase content shown the remanence ratio, Mr/Ms ≥ 0.5. The best result is from nanocomposite with 20 wt.% soft phase with the values of Hc and Ms are 3313.7 G and 36.3 emu/g, respectively. While, for physical mixing, the nanocomposites with 10-30 wt.% of soft phase content shows Mr/Ms ≥ 0.5. With the best result is from nanocomposite ferrite with 30 wt.% soft phase with the values of Hc and Ms are 2926.3 G and 45.5 emu/g, respectively. We also manage to get the average particle size for the nanocomposites < 50 nm for both methods. From the results, it is found that the exchange coupling in the nanocomposites is affected by the phase distribution between the hard and soft phases as the amount of soft phase increase in the nanocomposite, the coercivity and magnetization decrease. For example, the magnetization for the nanocomposites prepared by physical mixing method decrease from 45.5 to 5.0 emu/g for nanocomposite with 30-100 wt.% of soft phase content. The optimum amount of soft phase needed in the nanocomposite is found to be 20-30 wt.% to maximize the effect of the exchange coupling between the hard and soft ferrites. Nanocomposites (Materials) - Magnetic properties Nanocomposites (Materials) Ferrites (Magnetic materials) 2019-03 Thesis http://psasir.upm.edu.my/id/eprint/90029/ http://psasir.upm.edu.my/id/eprint/90029/1/FS%202019%2082%20ir.pdf text en public masters Universiti Putra Malaysia Nanocomposites (Materials) - Magnetic properties Nanocomposites (Materials) Ferrites (Magnetic materials) Mohd Saiden, Norlaily
institution Universiti Putra Malaysia
collection PSAS Institutional Repository
language English
advisor Mohd Saiden, Norlaily
topic Nanocomposites (Materials) - Magnetic properties
Nanocomposites (Materials)
Ferrites (Magnetic materials)
spellingShingle Nanocomposites (Materials) - Magnetic properties
Nanocomposites (Materials)
Ferrites (Magnetic materials)
Ahmad, Aisyah Radhiah
Phase distribution and magnetic properties of hard/soft ferrite nanocomposites prepared through mechanical alloying and physical mixing method
description Nanocomposite magnet consisting of hard and soft magnetic phases has attracted many attentions from the researcher in recent years. The exchange coupling between hard and soft phase can combine the high coercivity of the hard phase and the high magnetization of soft phase to produce a magnet with high energy product. The mechanical alloying and physical mixing method are chosen to produce the nanocomposite. The hard phase, SrFe12O19 and soft phase, Ni0.5Zn0.5Fe2O4 were mixed to become nanocomposite SrFe12O19/Ni0.5Zn0.5Fe2O4. The effect of phase distribution in the nanocomposite is studied by varying the amount of soft ferrite. While the amount of hard ferrite is kept constant. The novelty of this research lies in the different phase distribution between hard and soft phases in the nanocomposite, which gives more understanding of the effect of phase distribution on the exchange coupling. The characterizations of the samples are carried out using Thermogravimetric Analysis (TGA), X-ray Diffraction (XRD), Vibrating Sample Magnetometer (VSM), Electron Paramagnetic Resonance (EPR) and microstructure analysis using Transmission Electron Microscope (TEM) and Field Emission Scanning Electron Microscope (FESEM). The XRD results on the nanocomposites shown that both hard phase, SrFe12O19 and soft phase, Ni0.5Zn0.5Fe2O4 are present in the samples producing the SrFe12O19/Ni0.5Zn0.5Fe2O4 nanocomposite. From the mechanical alloying method, the nanocomposites with 10-20 wt.% of soft phase content shown the remanence ratio, Mr/Ms ≥ 0.5. The best result is from nanocomposite with 20 wt.% soft phase with the values of Hc and Ms are 3313.7 G and 36.3 emu/g, respectively. While, for physical mixing, the nanocomposites with 10-30 wt.% of soft phase content shows Mr/Ms ≥ 0.5. With the best result is from nanocomposite ferrite with 30 wt.% soft phase with the values of Hc and Ms are 2926.3 G and 45.5 emu/g, respectively. We also manage to get the average particle size for the nanocomposites < 50 nm for both methods. From the results, it is found that the exchange coupling in the nanocomposites is affected by the phase distribution between the hard and soft phases as the amount of soft phase increase in the nanocomposite, the coercivity and magnetization decrease. For example, the magnetization for the nanocomposites prepared by physical mixing method decrease from 45.5 to 5.0 emu/g for nanocomposite with 30-100 wt.% of soft phase content. The optimum amount of soft phase needed in the nanocomposite is found to be 20-30 wt.% to maximize the effect of the exchange coupling between the hard and soft ferrites.
format Thesis
qualification_level Master's degree
author Ahmad, Aisyah Radhiah
author_facet Ahmad, Aisyah Radhiah
author_sort Ahmad, Aisyah Radhiah
title Phase distribution and magnetic properties of hard/soft ferrite nanocomposites prepared through mechanical alloying and physical mixing method
title_short Phase distribution and magnetic properties of hard/soft ferrite nanocomposites prepared through mechanical alloying and physical mixing method
title_full Phase distribution and magnetic properties of hard/soft ferrite nanocomposites prepared through mechanical alloying and physical mixing method
title_fullStr Phase distribution and magnetic properties of hard/soft ferrite nanocomposites prepared through mechanical alloying and physical mixing method
title_full_unstemmed Phase distribution and magnetic properties of hard/soft ferrite nanocomposites prepared through mechanical alloying and physical mixing method
title_sort phase distribution and magnetic properties of hard/soft ferrite nanocomposites prepared through mechanical alloying and physical mixing method
granting_institution Universiti Putra Malaysia
publishDate 2019
url http://psasir.upm.edu.my/id/eprint/90029/1/FS%202019%2082%20ir.pdf
_version_ 1747813602573680640