85 research outputs found

    Influence of 1% addition of Nb and W on the relaxation process in classical Fe-based amorphous alloys

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    This paper features investigations into the influence of small additions of alloying elements on: structure, as well as the temporal and thermal stability of magnetic properties, and the disaccommodation effect, for the following amorphous alloys: Fe₆₁Co₁₀Y₈Me₁B₂₀ (where Me = Nb, W). The structure of the investigated samples has been confirmed by the Mössbauer spectroscopy. The obtained results indicate a strong correlation between the structure and the disaccommodation of the studied alloys. The Mössbauer studies reveal different configurations of atoms in the amorphous alloy samples, and the results indicate various potential barriers between orientations of atom pairs. For this reason, to describe the disaccommodation effect, the distribution of activation energy should be taken into account. The distribution of activation energy has been related to the distribution of relaxation times

    Analysis of the Thermal and Magnetic Properties of Amorphous Fe 61Co10Zr2.5Hf2.5Me2W2B20 (Where Me = Mo, Nb, Ni Or Y) Ribbons

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    The paper presents the results of structural and magnetic properties and thermal stability for a group of functional materials based on Fe61Co10Zr2.5Hf2.5Me2W2B20 (where Me = Mo, Nb, Ni or Y). Samples were obtained in the form of ribbons using melt-spinning method. The X-ray diffraction patterns of investigated samples confirmed their amorphous structure. Based on the analysis of DSC curves characteristic temperatures: glass forming temperature (Tg), crystallization temperature (Tx) and temperature range of the supercooled liquid ΔTx were determined. Small addition of transition metals elements has strong influence on magnetic and thermal parameters of studied materials. The comprehensive studies revealed that in terms of magnetic properties the Ni-addition resulted in highest reduction in coercivity and anisotropy field

    Magnetic Properties of the Rapidly Solidified Bulk Alloy: Fe61Co10B20Y8xWyPtxFe_{61}Co_{10}B_{20}Y_{8-x}W_{y}Pt_{x} (where: x=1,2; y=0,1)

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    In the literature, research into rapidly cooled Pt-based alloys usually features samples that are produced in the form of thin ribbons. This work presents the effect of the addition of a small quantity of W and Pt on the magnetic properties of massive two-phase alloys, the samples being produced in the form of plates with a thickness of 0.5 mm. Both amorphous and crystalline phases were observed in the alloys, the phase proportions depending on the composition of the alloy. Generally, it is assumed that alloys with added Pt are characterised by a relatively high saturation magnetization and magnetocrystalline anisotropy, which is mainly influenced by the presence of the crystalline phases: FePt and Fe₃Pt. For the investigated alloys, it was noted that the gradual substitution of W and Pt in place of Y within the alloy Fe61Co10B20Y8xWyPtxFe₆₁Co₁₀B₂₀Y_{8-x}W_{y}Pt_{x} increased the value of saturation magnetization (μ0Ms)(μ₀M_{s}) and reduced the coercive field (Hc)(H_{c}). On the basis of XRD pattern analysis it was found that, within the sample with the highest concentration of Pt, there are crystallites of the smallest size and the proportion of the α-Fe crystalline phase is much greater than for the other studied samples

    Microstructure and magnetic properties of the classical amorphous alloys: Fe₆₁Co₁₀Y₈Me₁B₂₀ (where Me = W, Mo)

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    A study has been conducted into the effects of substituting small quantities of alloying elements (tungsten and molybdenum) on the structure and magnetic properties of classical amorphous alloys that are based on the formula: Fe₆₁Co₁₀Y₈Me₁B₂₀. The structure of the resulting alloy samples was examined using X-ray diffraction, Mössbauer spectroscopy, and scanning electron microscopy. Based on the results of these studies, it was found that the obtained alloys were amorphous. Images from the scanning electron microscope were typical for amorphous materials. Cross-sectional images were homogeneous and did not contain "vein- and scale-type" precipitations. Studies examining the magnetic properties of the samples were carried out using a vibrating sample magnetometer. It was found that the alloy featuring the addition of tungsten exhibited a significantly greater saturation of magnetization and a substantially lower coercivity. This resulted from the fact that the atomic radius of tungsten is much larger than that of molybdenum, resulting in increased difference between the atomic constituents of the alloy; This, in turn, improves the glass-forming ability

    Analysis of the Thermal and Magnetic Properties of Amorphous Ribbons of Fe₆₁Co₁₀B₂₀Y₈Me₁ (where Me = W, Zr, Nb, Mo)

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    This paper presents the results pertaining to thermal and magnetic studies of rapidly-cooled samples of the alloy family Fe₆₁Co₁₀B₂₀Y₈Me₁ (where Me = Nb, Zr, W, Mo). The resulting ribbons, or tapes, have amorphous structure. It has been found that the addition of Me elements alters the thermal and magnetic properties. It is noted that the saturation magnetization decreases with increasing number of unpaired electrons on the valence shells. In addition, the value of the coercivity and effective anisotropy have been determined

    Effect of Selected Alloying Elements on the Soft-Magnetic and Mechanical Properties of Injection-Cast Fe61Co10Y8Me1B20 Alloys (Me = Nb, W or Mo)

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    Properties of amorphous alloys differ from each other when they are produced at different cooling rates and from different chemical compositions. This paper presents studies of the magnetic and mechanical properties of Fe61Co10 Y8 Nb1 B20, Fe61 Co10 Y8 -W1 B20 and Fe61 Co10 Y8 Mo1 B20 alloys, in the form of plates, produced by the injection of liquid alloy into a copper mould. Based on the performed studies, it was found that the substitution of 1% non-magnetic additive into the alloy composition had little effect, as regards the values of saturation magnetization (Ms ) and Curie temperature (Tc ). However, in the case of the coercive field, the sample with the W addition had a value almost half that of the other two alloys. For all of the studied alloys, the microhardness was about 1180 μHv100, i.e. significantly higher than for the same materials in the crystalline state

    Influence of polymer content on the magnetic properties of the Fe60Co10Y8W1B20 amorphous powders

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    W pracy przedstawiono wyniki badań kompozytów składających z ferromagnetyka Fe61Co10Y8W1B20 wykazującego miękkie właściwości magnetyczne związanego polimerem (Epidian 100) w proporcjach 2%, 3% i 4% wag. Przeprowadzono badania struktury wykorzystując dyfrakcje promieni rentgenowskich. Na podstawie tych badań wykazano że proces mielenia jak i utwardzania Epidianu w nie wpływa na strukturę badanych kompozytów powodując jej krystalizację. W kolejnym etapie przeprowadzono badania magnetyczne wykorzystując magnetometr wibracyjny (VSM). Pokazano, że można sterować właściwościami poprzez odpowiednie dobranie zawartości osnowy polimerowej.This paper presents results of research on the composites consisting of ferromagnetic Fe61Co10Y8W1B20 alloy exhibiting soft magnetic properties of bonded polymer (Epidian 100) in the proportion of 2%, 3% and 4% by weight. Structure study was carried out using X-ray diffraction. This research have shown that the process of grinding and Epidianu hardening does not affect the structure of the composites causing its crystallization. In a next step were studied by using a vibrating sample magnetometer (VSM). It is shown that the properties can be controlled through appropriate selection of the content of the polymer matrix

    The influence of powder fraction on magnetic and mechanical properties of a resin bonded composite made from amorphous metallic Fe60Co10Y8W1B20 powder

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    W pracy badano wpływ wielkości frakcji amorficznego proszku wiązanego polimerem na właściwości magnetycznie miękkie i mechaniczne. Proszek został otrzymany poprzez niskoenergetyczne mielenie amorficznej płytki wytworzonej metodą wtłaczania ciekłego stopu do miedzianej formy. Na podstawie badań dyfrakcji promieni rentgenowskich stwierdzono, że kompozyty miały strukturę amorficzną. Wykorzystując magnetometr wibracyjny zmierzono statyczne pętle histerezy magnetycznej, na podstawie których wyznaczono parametry takie jak: magnetyzacja nasycenia (μoMs.) oraz pole koercji (Hc). Zmierzono mikrotwardość wykorzystując metodę Vickersa. Na podstawie przeprowadzonych badań stwierdzono, że wielkość amorficznych cząstek istotnie wpływa na zmianę parametrów magnetycznych jak i mechanicznych badanych kompozytów. Dodatkowo stwierdzono, że osnowa polimerowa izolująca amorficzne cząstki wpłynęła na pogorszenie parametrów magnetycznie miękkich w porównaniu do masywnych płytek.In the paper investigates the effect of the volume fraction of amorphous powders on the soft magnetic and mechanical properties. The powder was obtained by low-energy milling of amorphous plates produced by the injection of a liquid alloy into a copper mold. On the basis of X-ray diffraction, it was found that the composites had an amorphous structure. Using the vibrating sample magnetometer, the static hysteresis loops were measured, on which basis the basic magnetic parameters such as saturation magnetization (μoMs) and the coercive field (Hc) were determined. Microhardness was measured using the Vickers method. From the examinations, it was found that the size of the amorphous particles significantly influences the change of magnetic and mechanical parameters of the studied composites. Additionally it was found that the polymeric matrix insulating the amorphous particles affected the deterioration of soft magnetic parameters in comparison to the massive plates

    The surface structural and mechanical properties of the amorphous CO22Y54AL24 ribbon

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    The aim of this study was to manufacture amorphous Co22Y54Al24 alloy in a form of thin ribbons and to investigate their properties. The investigated ribbons were prepared by rapid solidification of molten metal on a rotating copper cylinder (melt-spinning). In order to obtain the material with amorphous structure, the cooling rate of the liquid alloy should vary in a range from 104 to 106 K/s. The microstructure studies were performed using X-ray diffractometery. The mechanical properties were investigated by metallographic studies, micro-hardness and tribological resistance tests moreover the surface roughness profile were analyzed. All studies were performed for two sides of tapes, since the differences in ribbons surface, related with manufacturing process, are clearly visible. The surface from the bottom (drum side) was glossy and from the top side it was shiny
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