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Mechanism of thermal radiation, soret-dufour on ferromagnetic hybrid nanofluid through a permeable surface
(2025-04-01)
Krishnaveni, T. Radha
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Ramana Reddy, G. Venkata
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Anitha, J.
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Kumar, G. Charan
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Rajagopalan, N. R.
Mechanisms of thermal radiation, Soret-Dufour on Ferromagnetic hybrid nanofluid through a permeable surface has been considered in this paper. The higher thermal condition of the hybrid nanofluid was discussed alongside an induced magnetism. A partial differential equation (PDEs) has been used to describe the physical problem. The set of modeled PDEs was changed into ordinary differential equations and solved numerically using the spectral relaxation method (SRM). The outcome of the numerical simulations was presented graphically. The thermal radiation was discovered to greatly influence the thermal condition of the hybrid nanofluid. It was observed that the Soret term enhances the concentration layer while the Dufour term enhances the temperature layer. The outcome of this study was compared with previous work and found to be in good agreement.
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INFLUENCE OF SINTERING TEMPERATURES ON MULTIFERROIC PROPERTIES OF LEAD-FREE BNT-BT-NZF MULTIFERROIC COMPOSITE FABRICATED VIA THE SOLID-STATE COMBUSTION TECHNIQUE
(2025-01-01)
Chongsatan, Wistsarut
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Boonpluk, Wiranchana
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Vittayakorn, Naratip
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Pinitsoontorn, Supree
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Jantaratana, Pongsakorn
There has been a growing interest in multiferroics, materials that combine magnetic and electric ordering, over the past few years. This research investigates the influence of sintering temperature (1075-1175°C for 2 hours) on multiferroic properties of 0.7(0.94Bi<inf>0.5</inf>Na<inf>0.5</inf>TiO<inf>3</inf>-0.06BaTiO<inf>3</inf>)-0.3(Ni<inf>0.7</inf>Zn<inf>0.3</inf>Fe<inf>2</inf>O<inf>4</inf>) (BNT-BT-NZF) multiferroic composites, fabricated using solid-state combustion with glycine as a fuel was investigated. The XRD patterns of all ceramics revealed the coexistence of a rhombohedral ferroelectric phase, a tetragonal ferroelectric phase, and a cubic ferromagnetic phase. The average grain size, dielectric constant (ε<inf>r</inf>), dielectric loss (tanδ), remnant polarization (P<inf>r</inf>), and coercive field (E<inf>c</inf>) tended to increase from 0.66 to 2.5μm, 314 to 829, 0.22 to 0.51, 0.36 to 5.82 μC/cm2, and 7.05 to 26.96 kV/cm, respectively, with increase of sintering temperature. The composite ceramics exhibited peak saturation magnetization (M<inf>s</inf> ~ 12.21 emu/g) and magnetoelectric (ME) coupling (~ 3.59 mV/cmOe) when sintered at 1150°C.
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ELECTRIC AND MAGNETIC PROPERTIES OF Ba0.97Ca0.03Ti0.94Sn0.06O3-Mn0.85Ni0.15Zn0.15Fe2O4 MULTIFERROIC CERAMIC COMPOSITES FABRICATED VIA THE SOLID-STATE COMBUSTION TECHNIQUE
(2025-01-01)
Sonchaopria, Nutkamon
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Meechob, Jirayut
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Thatawong, Bhoowadol
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Vittayakorn, Naratip
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Pinitsoontorn, Supree
Multiferroic composites with the general formula (1-x)(Ba0.97Ca0.03Ti0.94Sn0.06O3)-x(Mn0.85Ni0.15Zn0.15Fe2O4) (BCTS/MNZF) (x = 0.1, 0.2, 0.3, 0.4, and 0.5) were prepared using the solid-state combustion method. The structure, morphology, dielectric, ferroelectric, magnetic, and magnetoelectric properties were analyzed. The samples were sintered at 1,300ºC for 2 h. The X-ray Diffraction (XRD) patterns revealed tetragonal perovskite, orthorhombic perovskite, and cubic spinel structures corresponding to the BCTS and MNZF phases. Secondary phases (Mn2O3 and SnO) appeared in the sintered samples with x>0.2. Increasing MNZF content enhanced ferrite grain growth in the composites. The dielectric constant showed an overall decreasing trend with increasing MNZF content, with a smaller effect at lower frequencies. At lower frequencies, the dielectric constant declined with increasing frequency before stabilizing around 10 kHz. As ferrite content increased, the density, dielectric constant, and magnetoelectric coefficient (αME) decreased from 5.66 to 5.12 g/cm³, 1388 to 862, and 7.24 to 4.05 mV/cm·Oe, respectively. While the saturation magnetization (Ms) rose substantially from 0.75 to 13.14 emu/g. These findings offer valuable insights into enhancing lead-free multiferroic composite ceramics for targeted applications in magnetoelectric devices.
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ELECTRICAL AND MAGNETIC PROPERTIES OF MULTIFERROIC Co0.6Zn0.4Fe1.7Mn0.3O4 DOPED 0.99Bi0.47Na0.47Ba0.06TiO3-0.01Ba(Sn0.70Nb0.24)O3 CERAMICS SYNTHESIZED VIA THE SOLID-STATE COMBUSTION TECHNIQUE
(2025-01-01)
Luangpangai, Anupong
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Chuai, Phomphon
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Rittidech, Aurawan
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Pinitsoontorn, Supree
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Jantaratana, Pongsakorn
Multiferroic (1-x)[0.99Bi<inf>0.47</inf>Na<inf>0.47</inf>Ba<inf>0.06</inf>TiO<inf>3</inf>-<inf>0.01</inf>Ba(Sn<inf>0.70</inf>Nb<inf>0.24</inf>)O<inf>3</inf>]-xCo<inf>0.6Z</inf>n<inf>0.4</inf>Fe<inf>1.7</inf>Mn<inf>0.3</inf>O<inf>4</inf> (abbreviated as BNBT-BSN-xCZFMO) ceramics with x ranging from 0 to 0.20 were fabricated using the solid-state combustion technique. The effect of varying BNBT-BSN: CZFMO ratios on the phase structure, microstructure, electrical and magnetic properties was investigated. X-ray diffraction (XRD) analysis of pure BNBT-BSN showed a perovskite structure with rhombohedral and tetragonal phases. The doped BNBT-BSN-xCZFMO ceramics displayed coexisting rhombohedral, tetragonal, and cubic spinel phases, with the cubic spinel phase increasing when the CZFMO content increased. In addition, the XRD peaks shifted to higher angles as the CZFMO content increased, indicating a decrease in lattice parameters. The dielectric constant decreased with higher CZFMO content and higher frequencies. The pure BNBT-BSN ceramic exhibited a saturated P-E loop with a Pmax of 33.2 µC/cm2, Pr of 26.1 µC/cm2, and an Ec of 14.5 kV/cm. With increased CZFMO content, non-saturated and bloated P-E loops with lower Pmax, Pr, and Ec were observed, implying a rise in the leakage current. The addition of CZFMO induced ferromagnetic behavior in the ceramics, leading to an increase in Ms and a reduction in Hc as CZFMO content increased. The magnetoelectric coupling coefficient of BNBT-BSN-xCZFMO ceramics continuously increased with higher CZFMO content.
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Phase formation, electric and magnetic properties of multiferroic 0.7Ba0.9Ca0.1TiO3-0.3Ni0.6Zn0.4Fe2O4 composites ceramics synthesized by the solid-state combustion technique
(2025-01-01)
Sonchaopri, Nutkamon
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Somsri, Widchaya
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Chootin, Suphornphun
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Vittayakorn, Naratip
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Pinitsoontorn, Supree
Multiferroic composite materials have both ferroelectric and ferromagnetic properties. In addition, the electrical and magnetic properties of these ceramics are primarily affected by the preparation temperature. Therefore, this study investigates the effect of the sintering temperature on the phase structure, microstructure, electrical and magnetic properties of multiferroic 0.7Ba<inf>0.9</inf>Ca<inf>0.1</inf>TiO<inf>3</inf>-0.3Ni<inf>0.6</inf>Zn<inf>0.4</inf>Fe<inf>2</inf>O<inf>4</inf> (BCT-NZF) composite ceramics synthesized by the solid-state combustion technique. The samples were sintered in a range of 1250–1350 ºC for 2 h. The X-ray diffraction (XRD) analysis revealed that all ceramics exhibited coexisting phases, with tetragonal perovskite, orthorhombic perovskite and cubic spinel phases, suggesting a complex crystalline structure. The average grain size of the ferroelectric and ferrite grains increased from 0.59 to 1.41 µm and 0.67 to 3.13 µm, respectively, moreover, ε and tanδ at 1 MHz tended to increase from 257.4 to 572.3 and 0.05 to 0.24, respectively, with increased sintering temperature. Density and saturated magnetization (M<inf>s</inf>) increased from 5.36 to 5.45 g/cm3 and 19.36 to 20.38 emu/g, respectively, while remanent magnetization (M<inf>r</inf>) and coercivity (H<inf>d</inf><inf>c</inf>) decreased from 0.38 to 0.33 emu/g and 25.03 to 20.17 Oe, respectively, when the sintering temperature was increased from 1250 to 1300 °C. Above 1300 °C, the density and M<inf>s</inf> decreased, while M<inf>r</inf> and H<inf>d</inf><inf>c</inf> increased. With the optimum sintering temperature of 1300 °C, the multiferroic BCT-NZF composite ceramics exhibited the highest density (5.45 g/cm3), low leakage P-E loop, good magnetic properties (M<inf>s</inf> = 20.38 emu/g) and high magnetoelectric coupling (α<inf>ME</inf> = 4.03 mV/cm•Oe), indicating this ceramic was suitable for application in magnetoelectric devices.
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A simple route to synthesize ferromagnetic binary calcium iron pyrophosphate CaFeP2O2 using aqueous-acetone media
(2013-08-30)
Chaiyasith, Pachernchaipat
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Ruttanapun, Chesta
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Thongkam, Montree
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Kongteweelert, Samart
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Woramongkonchai, Somsak
A binary calcium iron pyrophosphate CaFeP<inf>2</inf>O<inf>7</inf> was synthesized by solid state route using the mixing of calcium carbonate, iron metal and phosphoric acid in aqueous-acetone media at 600°C. The XRD datum indicates the formation of CaFeP<inf>2</inf>O<inf>7</inf> phase without the presence of any phase impurities. FTIR result indicates the presence of the P<inf>2</inf>O<inf>7</inf> 4- anion in the structure. Sheet-like microparticle of CaFeP<inf>2</inf>O<inf>7</inf> was revealed by SEM. Room temperature magnetization result showed ferromagnetic behavior of the synthesized CaFeP<inf>2</inf>O<inf>7</inf>, with saturation-specific magnetization value of 11.067 emu g-1 at 10kOe. The magnetic feature of the synthesized CaFeP<inf>2</inf>O<inf>7</inf> in this work compared with M<inf>2</inf>P<inf>2</inf>O<inf>7</inf> (M = Ca and Fe), its isotypic (CaMP2O7 (M= Mn and Co) and CFeP<inf>2</inf>O<inf>7</inf> (C= Co and Cu) reported in our previous works is important properties for specific applications. © (2013) Trans Tech Publications, Switzerland.
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Ferroelectric and ferromagnetic properties of K-doped 0.7BiFeO 3-0.3BaTiO3 multiferroic ceramics
(2013-01-01)
Prasatkhetragarn, A.
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Jantaratana, P.
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Vittayakorn, N.
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Yotburut, B.
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Yimnirun, R.
Lead-free and multiferroic 0.7BiFeO<inf>3-</inf>0.3BaTiO<inf>3</inf> ceramics doped with K (0.5, 1.0, 3.0 and 5.0 mol%) have been successfully prepared by a solid state mechanical milling technique. The single phase perovskite was found at calcination temperature of 900?C for 6 h. The effects of K doping on the crystal structure, microstructure, magnetic and electrical properties of lead-free 0.7BiFeO<inf>3-</inf>0.3BaTiO<inf>3</inf> ceramics were investigated and discussed. The fracture micrographs of specimens elucidate the grain growth behavior with increasing K content up to 3.0 mol%. The weak ferromagnetic and ferroelectric properties were observed in rhombohedrally- distorted 0.7BiFeO<inf>3-</inf>0.3BaTiO<inf>3</inf> perovskite ceramic. However, the addition of K into 0.7BiFeO<inf>3-</inf>0.3BaTiO<inf>3</inf> has been found to improve the ferroelectric and ferromagnetic properties, with the optimized properties obtained at 3.0 mol% content of K. Copyright © 2013 Taylor & Francis Group, LLC.
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Synthesis and ferromagnetic property of new binary copper iron pyrophosphate CuFeP2O7
(2010-02-15)
Boonchom, Banjong
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Vittayakorn, Naratip
The pyrophosphate of CuFeP<inf>2</inf>O<inf>7</inf> was synthesized through one step-thermal synthesis at 500 °C using the mixing of copper carbonate, iron metals and phosphoric acid. FTIR and XRD results indicate the dominant feature of pyrophosphate (P<inf>2</inf>O<inf>7</inf>4-) anion and a pure monoclinic phase with space group C<inf>2h</inf>6 (Z = 4), respectively. The crystallite size of 25 ± 9 nm for the CuFeP<inf>2</inf>O<inf>7</inf> was estimated by X-ray line broadening. Room temperature magnetization result shows ferromagnetic behavior of the CuFeP<inf>2</inf>O<inf>7</inf> powder, having hysteresis loop in the range of ± 10,000 Oe with the specific magnetization value of 1.57 emu g- 1. This property is important for specific application and is presented for the first time. © 2009 Elsevier B.V. All rights reserved.

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