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Series of Ni45.5-xCo4.5Mn36.6In13.4Bx (at.%, x = 0, 0.05, 0.1, 0.5, 1.0) polycrystalline magnetic shape memory alloys were examined in terms of the magnetic properties, structure and transition temperatures. Depending on the boron concentration single or two phase alloys microstructures were observed. Additionally, the martensitic transformation temperatures decreases with the boron addition. Magnetic-field induced transformation occurs for the alloys with the boron addition up to 0.1 at.%. For alloys with 0.5 and 1.0 at.% of B transformation is hindered. [ABSTRACT FROM AUTHOR]

In the present paper the Co1-δZnδFe2O4 (0 ≤ δ ≤ 1) ferrite nanopowders with a spinel type structure were synthesized using a chemical co-precipitation technique with constant flow rate VFR = 120 cm3/min at three different reaction temperatures i.e. Tτ = 50 °C, 70 °C and 90 °C. Magnetic and structural characteristics of the obtained materials were investigated by means of X-ray diffraction method, transmission electron microscopy and vibrating sample magnetometer. In the course of studies hysteresis loops M(μ0H) and the relations of magnetization M7T (determined at μ0H = 7T), squareness ratio S and the Néel temperature TN versus Zn content were determined and discussed in detail. It was shown that for δ < 0:6 the increase in reaction temperature Tτ results in a significant increase of the measured magnetic characteristics. In particular, in the case of Co0.8Zn0.2Fe2O4 ferrite nanopowder magnetization M7T reaches maximal value of about 80 emu/g. [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]

The paper is focused on the magnetic and structural properties of RCo5 (R = Y, Gd, Sm) intermetallics fabricated by high energy ball - milling (HEBM). The investigated samples were first produced by arc-melting as bulk materials and then were milled for 1h in dimethylformamide with balls to powder ratio 10:1. The influence of the HEBM parameters on the microstructure was investigated by a variety of complementary measurement methods. The Rietveld refinement was performed to estimate the dependence of crystallite size and microstrain on type of sample. The hysteresis loops were recorded by SQUID magnetometer at 2 K and 300 K and at magnetic field up to μ0H = 7 T. The impact of short HEBM process is visible as the enhancement of coercivity and simultaneous reduction of the saturation magnetization. [ABSTRACT FROM AUTHOR]

The influence of substitution of Co for Ni in Sm(Ni1-xCox)3, where x = 0:0, 0,1, 0.2, on the structural and magnetic properties has been investigated. Samples with x = 0:0 and 0.2 were subjected to grinding in a high energy ball mill. The presence of a PuNi3 type of crystal phase was evidenced for bulk crystalline and powders specimens. With an increase in the cobalt content, an increase at Tc was observed. From the magnetic isotherms, the magnetic entropy changes were determined both for solid and powdered samples. It has been shown that the value of the magnetic entropy change at Tc is doubled for the bulk sample with x = 0.2 but it has decreased significantly for all powdered samples. [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]

Series of Ni45.5-xCo4.5Mn36.6In13.4Bx (at.%, x = 0, 0.05, 0.1, 0.5, 1.0) polycrystalline magnetic shape memory alloys produced by the induction melting were examined in terms of the structure and transition temperatures. The structure of the alloys was determined by the X-ray diffraction and transmission electron microscopy. Scanning electron microscopy and electron backscattering diffraction techniques were applied to obtain the microstructure and texture of alloys. Boron addition promotes nucleation of the second Co-rich and In-poor phase as well as causes decrease of the martensitic transformation temperatures. [ABSTRACT FROM AUTHOR]

In the paper we present and discuss magnetic properties of the Tb(Ni1–xFex)3 (x = 0:2, 0.6) crystalline compounds and their ball-milled powders. The investigated samples are polycrystalline and crystallize in the rhombohedral PuNi3 type of crystal structure. The Curie temperature of the material seems to be independent of particle size and is constant. The coercivity depends on the amount of iron dopant. The saturation magnetization decreases after mechanical grinding which is connected with the reduction in particle size. After 6 h milling time the SEM results show the presence of nanoflakes with thickness up to 100 nm or even smaller. Moreover, the pulverization leads to the observed decrease of magnetocaloric effect. [ABSTRACT FROM AUTHOR]