16 research outputs found
Needle-less electrospinning employed for calcium and magnesium phosphate coatings on titanium substrates
Needle-less electrospinning employed for calcium and magnesium phosphate coatings on titanium substrates
Preparation and Investigations of Ferrite Nanofiber Membranes by Needleless Electrospinning Method
The preparation of nanofiber membranes by simple and versatile needleless electrospinning technique is presented. The single phase of spinel ferrite membrane was obtained after conventional thermal treatment of polyvinyl alcohol (PVA)/metal nitrate precursors at 800°C for 4 h in air. The formation of single-phase fibers was characterized using differential scanning calorimetry accompanied with thermogravimetric analysis. The surface morphology, microstructure and crystal structure were investigated by scanning electron microscopy, X-ray diffraction and transmission electron microscopy. The magnetic properties of the fibrous samples measured in the temperature range from 2 to 300 K verify a soft magnetic behavior, which is quite typical for ferrimagnetic spinel-type ferrites
Imaging of Magnetic Domain Structure in Composite using Magnetic Force Microscopy
Soft magnetic composite was prepared by coating the commercial FeSi powder by (MnZn) ferrite, which serves as a potential dielectric phase. MnZn ferrite was prepared by the sol-gel method followed by the auto-self combustion process. The spinel structure of MnZn ferrite was analyzed by X-ray diffraction technique. The composite material was prepared by uniaxial compaction technique and sintered either by conventional or unconventional microwave method. The microwave sintering was applied in order to reduce a grain growth and decrease the overall sintering time. The microstructure of FeSi powder is formed by grains of different diameter. Magnetic force microscopy and scanning electron microscopy were used for an investigation of the correlation between the grain size, grain boundaries and magnetic domains. Magnetic force microscopy visualization of magnetic domains in the prepared soft magnetic composite brings insight into how the magnetically active coating (MnZn ferrite) influences the soft magnetic (FeSi) powder under the influence of the external magnetic field