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In this article, magnetic and structural characteristics of CoFe2O4 nanopowders with mean diameter 17.8(4) and 63.7(2.4) nm [denoted as NM(18) and CP(60), respectively] were studied by applying X-ray diffraction method (XRD), transmission electron microscopy (TEM), and vibrating sample magnetometer (VSM). It was established that for NM(18), the nanoparticle size corresponds to one crystallite while CP(60) nanoparticle forms a multi-crystallite system which means certain kind of averaging of magnetic moments. Magnetic analysis was performed according to the ZFC-FC protocol in the temperature range of 10–380 K, and magnetization curves $M(H)$ were recorded at the magnetic field up to 7 T. It was shown that, independently on nanoparticle size distribution, the magnetic response of both nanopowders is mainly determined by superspin glass type interaction of magnetic moments corresponding to a single crystallite. In addition, basic magnetic characteristics such as anisotropy constant $K_{1} =$ (3.9–12.5) $\times 10^{5}$ J/ $\text{m}^{3}$ , anisotropy field $\mu _{0}H_{\mathrm {A}} = 1.80$ –5.80 T, or magnetic moment per formula unit $\mu =3.45$ (5) $\mu _{\mathrm {B}}$ [for CP(60)] and $\mu =3.50$ (5) $\mu _{\mathrm {B}}$ [for NM(18)] were also determined and discussed. [ABSTRACT FROM AUTHOR]

Nickel-free titanium alloys are a promising research direction in the field of biomedical materials. Current literature reports indicate that there is a possibility of using the Ti-Ta alloys in medicine since these alloys have had satisfactory results as far as biocompatibility, resistance to corrosion and mechanical properties are concerned, which is an important aspect while considering the use of this alloy for long-lasting bone implants. This article presents the results of a high-energy milling process with the use of Ti and Ta powders. The ball-milling process was carried out for various times, including 20, 40, 60, 80, and 100 h. The samples were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The research confirmed partial synthesis of the materials during the process of high energy ball milling. [ABSTRACT FROM AUTHOR]

Hot extrusion process was applied to Ni54.3Fe16.2Ga29.5 polycrystalline alloy. Then the rod was annealed subsequently for 1 h at 700, 800, 900, and 1100 °C. In this paper the effect of annealing on the microstructure of the polycrystalline extruded Ni-Fe-Ga alloy were analyzed. The structure of the alloys was determined by the X-ray and transmission electron microscopy. The electron backscattering diffraction technique was applied to obtain the texture of the extruded rods after heat treatment. [ABSTRACT FROM AUTHOR]