Structure,Texture and Magnetic Properties of Laser-Welded Ultrathin Fe-Co-V Foils

This research aims to investigate the effect of pulsed Nd：YAG laser micro-welding on the microstructure,texture and magnetic properties of ultra-thin Fe-Co-7.15 wt%V magnetic alloy.Optical microscopy,scanning electron microscopy and electron backscattered diffraction techniques were used to study the microstructural evolutions.Also,vibrating sample magnetometry was used to characterize the magnetic properties.The results showed that the fractions of low Σ coincidence site lattice boundaries in the fusion zone are higher than those of the base metal.The welded samples experience a significant decrease in their magnetic properties.It was found that the formation of new fiber texture in the fusion zone and grain coarsening are the most important factors affecting the magnetic properties.

DISTRIBUTION OF MOMENTS AND MAGNETIZATION AXES IN MAGNETIC RECORDING TAPES

As concerns the magnetic recording media made of acicular γ-Fe2O3 particles, the squareness S=M/M,, which depends on the angular distribution of easy magnetization axes of particles in the recording tapes, is a key parameter influencing its level of output symbols. There are a lot of investigations with magnetic measurement or M（?）ssbauer spectroscopy on the squareness and the angular distribution of magnetization axes in recording tapes.

Microstructure of polycrystalline Fe_(82)Ga_(18) sample with solidification texture

Main attention of this paper was devoted to studying the effect of solidification texture on microstructure（phase constituents,grain morphology,and magnetic domain structure） of polycrystalline Fe_（82）Ga_（18） sample.The alloy was melted using button arc melting and solidified in water-cooled copper mold.Optical microscope（OM） results confirm the development of large columnar grains in the solidification microstructure.Phase constitution and magnetic domain structures of the sample were studied by X-ray diffraction（XRD） and magnetic force microscopy（MFM）.Results show a single-phase solid solution with an A2 structure for the sample which consists of regularly aligned magnetic domains.Although some maze-like subdomains are found in few regions,well-aligned stripe-like domains are predominant patterns in the sample.It demonstrates the high dependence of grain morphology and magnetic domain structure upon a preferred crystallographic direction during solidification.

Structure and Magnetic Properties of Magnetostrictive FeGa Film on Single-Crystal(100) GaAs and(001) Si Substrate Fabricated by Pulsed Laser Deposition

FeGa thin film has been deposited on（100）-oriented GaAs and（001）-oriented Si substrates with different film thicknesses and laser energy densities at room temperature by pulsed laser deposition system.Materials structure and static magnetic of FeGa film have great changes depending on the substrate and energy density of pulsed laser.X-ray diffraction reveals the presence of first-order order–disorder structure ofgrain phase and disordered bcc A2 structure on GaAs substrate.The coercivity and remanence of FeGa film on GaAs substrate ratio show a regular dependence on the thickness and energy densities.However,film on Si substrate did not exhibit structure change,which can be attributed to a large lattice mismatch between FeGa and Si.