The Influence of Milling Regimes in Beater Mill on Particle Size Distribution and Structural Characteristics of Strontium Hexaferrite Powder

Abstract:

The paper experimentally substantiates effectiveness of method of milling particulate ferromagnetic materials in magneto fluidized bed. Comparative results of particle size distributions and structural parameters of strontium hexaferrite SrFe₁₂O₁₉ powder obtained by milling coarse material in beater mill without electromagnetic effect and in same mill with formation of magneto fluidized bed from mill material are presented. The magneto fluidized bed is formed by constant and alternating gradient magnetic fields with induction lines that are mutually perpendicular and parallel to the plane of rotating beaters. It is shown that application of electromagnetic effect to milling coarse material in beater mill allowed to greatly intensify that process, significantly increase powder quality: increase particle size distribution uniformity and decrease average particle size from 1558.50 μm to 0.56 μm after 120 minutes of processing in the mill. X-ray diffraction analysis showed that milling in beater mill in magneto fluidized bed leads to reduction of coherent-scattering region size, increase of lattice microstrain and dislocation density, making powder more active during sintering process.

• Periodical: Solid State Phenomena (Volume 284)
• Pages: 158-162
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.284.158
• Online since: October 2018
• Authors: I.N. Yegorov*, Nikolay Ya. Egorov
• Keywords: Fluidized Bed, Microstructure, Milling, Particle Size Distribution

References

[1] J.G. Yates, P. Lettieri, Fluidized-bed reactors: processes and operating conditions, Springer International Publishing, (2016).

[2] I.N. Egorov, S.I. Egorova, Yu.M. Vernigorov, R.F. Pat 2306180. (2007).

[3] I.N. Egorov, N. Ya. Egorov, Technological processes intensification in devices with magneto-fluidized bed, MATEC Web Conferences. 132 (2017) 1-4.

DOI: 10.1051/matecconf/201713203001

[4] E.G. Avvakumov, Mechanical methods of chemical processes activation, Nauka, Novosibirsk, (1986).

[5] V.N. Antsiferov, L.M. Letyuk, V.G. Andreev, Problems of powder material science, Metallurgiya, Moscow, (2005).

[6] H.G. Merkus, G.M.Y. Meesters, Particulate products, Springer International Publishing, (2014).

[7] I.N. Egorov, Influence of electromagnetic effect during milling on ferromagnetic powders structural state, Technologiya metallov, 3 (2015) 34-40.

[8] I.N. Egorov, S. I. Egorova, Effect of electromagnetic action on dispersed composition on milling ferromagnetic materials in a hammer mill, Russian Journal of Non_Ferrous Metals, 55 (2014) 371-374.

DOI: 10.3103/s1067821214040063

[9] J. M. Millan, Fluidization of Fine Powders: Cohesive versus Dynamical Aggregation, Springer Netherlands, (2013).

[10] Information on: www.ccp14.ac.uk.

[11] H.M. Rietveld, Profile refinement method for nuclear and magnetic structures, J. Appl. Cryst. 2 (1969) 65-71.

[12] A. Ginye, X-ray diffraction on crystals, Gosudarstvennoe izdatelstvo fiziko-matematicheskoy literatury, Moscow, (1961).

[13] V.T. Bublik, A.N. Dubrovina, Semiconductors and metals structure research methods, Metallurgiya, Moscow, (1978).

[14] M.A. Krivoglaz, X-ray and neutron diffraction in imperfect crystals, Naukova dumka, Kiev, (1983).

[15] J.I. Langford, А rapid method for snalysing the breadths of diffraction and spectral lines using the Voigt function, J. Appl. Cryst. 11 (1978) 10-14.

DOI: 10.1107/s0021889878012601

[16] J.I. Langford, R. Delhez, Th.H. Keijser, E.J. Mittemeijer, Profile analysis for microcrystalline properties by the fourier and other methods, Aust. J. Phys. 41 (1988) 173-187.

DOI: 10.1071/ph880173

[17] S.S. Gorelik, L.N. Rastorguyev, Yu.A. Skakov, X-ray diffraction and electron optical analysis, Metallurgiya, Moscow, (1970).

[18] N.Ya. Egorov, I.N. Egorov, V.P. Kryzhanovskiy, A.I. Chernyi, Role of powder self-milling in magneto fluidized bed during milling in beater mill, EDUCATIO. 2 (2015) 41-44.

[19] C. Thornton, Granular Dynamics, Contact Mechanics and Particle System Simulations, Springer International Publishing, (2015).

[20] T. Porshel, T. Schwager, Computational Granular Dynamics, Springer-Verlag Berlin Heidelberg, (2005).