Abstract

Ni substituted M type calcium hexaferrite with composition CaNi_xFe_12-xO₁₉ (x = 0.5, 1.0, 1.5, 2.0) were synthesized by sol - gel auto combustion method. X-ray diffraction analysis confirms the phase composition of prepared samples and reveals that all the samples belong to M type hexaferrite. The crystallite size was determined by the Debye Scherrer formula and W-H Plot analysis method. Lattice parameters (‘a’ and ‘c’) and lattice volume increases with increase in Ni²⁺ ion concentration. Morphology of the samples was observed by scanning electron microscopes showing that all the prepared samples were hexagonal structure. The absorption band between 516 cm⁻¹–527 cm⁻¹ and 427 cm⁻¹–462 cm⁻¹ in the FTIR study confirms the formation of hexaferrite. With increasing Ni²⁺ ion concentration the peak position in FTIR and XRD was shifted toward lower frequency and lower angle. Energy-dispersive X-ray spectroscopy analysis confirms the presence of Fe, Ca, Ni and O in all the samples. Vibrating sample magnetometer was used to measure the magnetic parameters such as saturation magnetization, coercivity and remanent magnetization. Saturation magnetization increases from 8.845 emu/gm to 26.05 emu/gm, while the coercivity increases from 162.88 Oe to 184.67 Oe with increasing Ni²⁺ ion concentration from 0.5 to 2.0 make substituted hexaferrite material suitable for recording media.[AQ1]

摘要

 通过溶胶-凝胶自动燃烧法合成了具有CaNi _x Fe _12-x O ₁₉（x = 0.5，1.0，1.5，2.0）组成的Ni取代M型六方铁酸钙。X射线衍射分析证实了所制备样品的相组成，并揭示了所有样品均属于M型六方铁氧体。通过Debye Scherrer公式和WH图分析法确定微晶尺寸。晶格参数（“ a”和“ c”）和晶格体积随Ni ²⁺离子浓度的增加而增加。通过扫描电子显微镜观察样品的形态，显示所有制备的样品均为六边形结构。516 cm ^-1 –527 cm ^-1之间的吸收带FTIR研究中的427 cm ^-1 –462 cm ^-1证实了六铁素体的形成。随着Ni ²⁺离子浓度的增加，FTIR和XRD中的峰位置移向更低的频率和更低的角度。能量色散X射线光谱分析证实所有样品中均存在Fe，Ca，Ni和O。振动样品磁力计用于测量磁参数，例如饱和磁化强度，矫顽力和剩余磁化强度。Ni ²⁺离子浓度从0.5增加到2.0时，饱和磁化强度从8.845 emu / gm增加到26.05 emu / gm，矫顽力从162.88 Oe增加到184.67 Oe，使得取代的六价铁氧体材料适用于记录介质。[AQ1]