Investigating the Effect of α-Fe₂O₃ Oxides on the BaFe₂O₄ Pyrosynthesis Temperature - The Digital Processing of TG and DTA Curves

Abstract:

In the research activities on the barium monoferrite pyrosynthesis, an important place is occupied by TG and DTA analysis. The effects of different hematite (α-Fe₂O₃) granulations on the BaFe₂O₄ pyrosynthesis temperature were followed. Four types of commercial hematite powders were used, the difference between them being the fineness of the powder granules and the purity. Only one type of commercial barium carbonate (BaCO₃) powder was also used as a barium additive in the BaFe₂O₄ pyrosynthesis. Each of the 4 types of α-Fe₂O₃ with BaCO₃ were subjected to the homogenization process in a planetary mill for a more intimate mixing of the powders in order to obtain error-free results regarding the pyrosynthesis reaction. To determine BaFe₂O₄ pyrosynthesis temperature, a derivatograph device was used. All the data obtained with this thermal device were digitally processed in order to extract the two TG and DTA curves. The protective atmosphere in the furnace was nitrogen. BaFe₂O₄ pyrosynthesis temperatures recorded different values for the four mixtures, depending on the particle size of the α-Fe₂O₃ powders, protective atmosphere from furnace and the mixing conditions. The effects of Fe₂O₃ oxides on the BaFe₂O₄ pyrosynthesis temperature is observed when are used very fine hematite powders in mixtures, obtaining a reduction of pyrosynthesis temperature up to 16% compared to the mixture where the size of the hematite is coarser.

• Periodical: Advanced Engineering Forum (Volume 42)
• Pages: 42-49
• DOI: https://doi.org/10.4028/www.scientific.net/AEF.42.42
• Online since: September 2021
• Authors: Iulian Ştefan*, Gabriel Constantin Benga, Ionel Dănuț Savu, Sorin Vasile Savu, Bebe Adrian Olei
• Keywords: Barium Monoferrite, Hematite, Pyrosynthesis Temperature

References

[1] I. Ali, M.U. Islam, M.S. Awan, M. Ahmad, Effects of Heat-Treatment Time on the Structural, Dielectric, Electrical, and Magnetic Properties of BaM Hexaferrite, Journal of Materials Engineering and Performance (2013) 22:2104–2114.

DOI: 10.1007/s11665-013-0484-4

[2] A. Goldman, Modern Ferrite Technology, 2nd edition, Springer, (2006).

[3] I. Ştefan, S. Savu, O. Ghermec, C. Nicolicescu, M. Trotea, Researches regarding elaboration of barium hexaferrite from microwave heating, Solid State Phenomena Vol. 188 (2012) pp.369-375.

DOI: 10.4028/www.scientific.net/ssp.188.369

[4] R.C Pullar, A.K. Bhattacharya, Crystallisation of hexagonal M ferrites from a stoichiometric sol–gel precursor, without formation of the α-BaFe2O4 intermediate phase, Materials Letters, Volume 57, Issue 3, (2002) pp.537-542.

DOI: 10.1016/s0167-577x(02)00825-x

[5] S.-Y. Shen, H. Zheng , P. Zheng, Q. Wu, J.-X. Deng, Z.-H. Ying, L. Zheng, Microstructure, magnetic properties of hexagonal barium ferrite powder based on calcination temperature and holding time, Rare Met., (2018) https://doi.org/10.1007/s12598-018-1153-4.

DOI: 10.1007/s12598-018-1153-4

[6] L.-H. Shao, S.-Y. Shen, H. Zheng, P. Zheng, Q. Wu, L. Zheng, Effect of Powder Grain Size on Microstructure and Magnetic Properties of Hexagonal Barium Ferrite Ceramic, Journal of Electronic Materials, Vol. 47, No. 7, (2018) pp.4085-4089.

DOI: 10.1007/s11664-018-6301-y

[7] S. Anjum, F. Sehar, Z. Mustafa, M. S. Awan, Enhancement of structural and magnetic properties of M-type hexaferrite permanent magnet based on synthesis temperature, Applied Physics A (2018) 124:49.

DOI: 10.1007/s00339-017-1456-6