Ni Sb Research Articles

A study of the NiSb interaction in a rare-earth Y-zeolite

Two series of catalysts were prepared by impregnating nickel and nickel-antimony over a rare-earth-exchanged Y-zeolite. The nickel loadings for the monometallic catalysts were within 0.00–1.00% in weight; for the bimetallic systems the Ni loadings were in the 0.10–0.99% range while the Sb loadings were within 0.042–0.84% in weight. The effect of Sb addition on the structure and chemisorptive properties of Ni was examined using reduction studies, CO and H 2 chemisorption, IR spectroscopy, and cracking of isooctane. Complete reduction to metallic nickel and metallic antimony was found for Ni- and Sb-rich catalysts. The addition of Sb dramatically decreased the chemisorption of H 2 and CO. Infrared results suggest the formation of a single species, probably a Ni(CO) x species, for high-loading (>0.3%) nickel catalysts (even after desorption of the gaseous CO at room temperature). For the NiSb catalysts the bands were much weaker (in the presence of gaseous CO) and practically disappeared after the evacuation procedure. The cracking of isooctane showed a considerable increase in the formation of coke and hydrogen with increasing Ni loadings. The presence of antimony restored the amounts of coke and hydrogen to the original values present in the unsupported zeolite. Site blockage of Ni by Sb and weakening of the NiC bond by the addition of Sb are suggested to explain the results.

Effect of Crystallographic Orientation on Contact Resistance of Electroplated Nickel Alloys

The contact resistance of electrodeposited nickel doped with Sb, In, Zn, and P on copper coupons has been studied. After accelerated aging at 35°C and 95% relative humidity for 7 days, nickel deposits with (111) or (220) preferred orientations exhibit no degradation in the contact resistance. However, deposits with the (100) preferred orientation show a large increase in the contact resistance. From an initial value of about 10 mΩ before aging, the contact resistance increases after aging fourfold in Ni(P) deposits and almost 20‐fold in Ni(Sb) deposits. This result is attributed to faster oxide film formation on the (100) plane than on the (111) planes. Furthermore, we suggest that the addition of dopant elements in the nickel bath increases the overvoltage to form the doped nickel deposits. Therefore, the orientation with the lowest overvoltage, namely, the (111), is formed from the doped nickel bath at the same current density as that at which the (100) orientation will form from a pure nickel bath. The transition from the (111) to the (100) preferred orientation occurs at a higher current density in the doped nickel baths.

Crystal structure and magnetic properties of some Mn2Sb‐based alloys

AbstractThe results of the investigation of structural and magnetic properties of the Mn2(Ni)Sb, Mn2(Cr,Cu)Sb Mn2(Ti,Zn)Sb alloys are reported. The solubility limits of the elements substituting Mn in the Mn2Sb matrix, keeping the crystal structure of the Cu2Sb(C38)‐type, are established and the lattice parameters temperatures of magnetic phase transitions, specific magnetization of the materials are determined. The influence of thermal treatment and thermal cycling on the magnetic properties of the alloys, which is interpreted by the quantitative redistribution, depending on temperature, of the amount of the main δ‐phase (C38) in the samples, with the phase composition changing, and that of an additional nickel‐arsenide ϵ‐phase has been found.

Anomalous concentration dependence of the resistivity of liquid NiSb alloys

The electrical resistivity of the liquid Ni x Sb (1−x) system has been measured by 10 at % steps from pure antimony to 50 at % nickel. The resistivity shows clearly a minimum in the concentration dependence at about 30 at % nickel; followed by a maximum for nickel alloys. The resistivity is interpreted and discussed with the t-matrix formulation using hard-sphere structure factors.

Mineralogical Characterization of Anode Slimes: Part V—Nickel-Rich Copper Anodes from the CCR Division of Noranda Minerals Inc.

Nickel-rich copper anodes from the CCR Division of Nor and a Minerals Inc. have been examined chemically and mineralogically to identify the phases present. Cuprous oxide, Cu2O, is the principal impurity phase, and this occurs either as spheroidal particles at the copper grain boundaries or as tubelike inclusions oriented perpendicular to the upper surface of the anode. Nickel exists in solid solution in the copper matrix, as NiO crystal inclusions, and as kupferg1immer (Cu–Ni–Sb oxide) inclusions in selenides; the presence of NiO and kupferglimmer depends on the Ni and Sb contents of the anodes. Iron is present in amounts ranging from 14–81 ppm, and the iron occurs in solid solution in the NiO inclusions or as rare NiFe2O4 (ferrite) crystals. Silver occurs mostly in solid solution in the copper matrix although lesser amounts are present in solid solution in copper selenide inclusions which are the dominant selenium, and tellurium, carrier in all the anodes studied. Anodes rich in As and Bi contain numerous inclusions of Cu–Bi–As oxide and Cu–Bi oxide as well as As– and Bi–rich complex Cu–Pb– As–Sb–Bi oxides. Notable is the presence of thin rims of metallic silver which surround copper selenides associated with the oxide inclusions, and especially, the bismuth-rich oxides. Although some of the lead is in solid solution in the copper matrix, the majority of this element exists as complex inclusions of Cu–Pb oxide, Cu–Pb–As oxide or Cu–Pb–As–Sb–Bi oxide. All of the impurities are present principally as tiny inclusions concentrated at the copper grain boundaries; in many instances the inclusions are <1 μm in size.

Mineralogical Characterization of Anode Slimes: Part V—Nickel-Rich Copper Anodes from the CCR Division of Noranda Minerals Inc.

AbstractNickel-rich copper anodes from the CCR Division of Nor and a Minerals Inc. have been examined chemically and mineralogically to identify the phases present. Cuprous oxide, Cu2O, is the principal impurity phase, and this occurs either as spheroidal particles at the copper grain boundaries or as tubelike inclusions oriented perpendicular to the upper surface of the anode. Nickel exists in solid solution in the copper matrix, as NiO crystal inclusions, and as kupferg1immer (Cu–Ni–Sb oxide) inclusions in selenides; the presence of NiO and kupferglimmer depends on the Ni and Sb contents of the anodes. Iron is present in amounts ranging from 14–81 ppm, and the iron occurs in solid solution in the NiO inclusions or as rare NiFe2O4 (ferrite) crystals. Silver occurs mostly in solid solution in the copper matrix although lesser amounts are present in solid solution in copper selenide inclusions which are the dominant selenium, and tellurium, carrier in all the anodes studied. Anodes rich in As and Bi contai...

Influence of cosegregation on grain boundary diffusion: Experimental study in ultra high purity FeNiSb solid solutions

We have studied the influence of cosegregation on grain boundary (G.B.) diffusion in FeSb and FeSbNi high purity solid solutions with radioactive tracers and Auger electron spectroscopy. Using these two techniques to measure respectively the grain boundary diffusivity and the G.B. composition, we were able to monitor the variations of the G.B. diffusion coefficients as a function of the G.B. chemical composition. We observe that antimony segregation (in FeSb) and antimony and nickel cosegregation (in FeNiSb) lead to a large decrease of the G.B. diffusion of the three species. This behavior is explained assuming a modification of the G.B. structure induced by the strong iron-antimony or nickel-antimony interactions. Iron and antimony G.B. diffusion coefficients are identical in Fe(Sb) and Fe(NiSb) when the G.B. concentration of antimony is the same: the presence of nickel just increases the G.B. antimony content. In ternary alloys the segregation of nickel excludes the iron atoms from the G.B. core. Adding nickel in pure iron strongly affects the antimony G.B. heterodiffusion. This clearly indicates that the dispersion observed in G.B. heterodiffusion measurements can be explained by cosegregation effects due to highly active impurities.

Solubility of antimony in cobalt, nickel and CoNi alloys

The solid solubility of antimony in cobalt, nickel and Co-Ni alloys has been examined by electron probe microanalysis. It has been ascertained that the solubility of antimony decreases abnormally below the Curie temperature. The compound phase γ-(Co, Ni)Sb equilibrates with the f.c.c. Co-Ni phase at less than 20% Ni, while β-(Ni, Co) 5Sb 2 appears in a region of higher nickel content. These experimental data have been analysed thermodynamically and the phase equilibria in the Co-Ni-Sb system below 50% Sb have been calculated.

The interactive co-segregation of Sb and Ni at the grain boundaries of ultra-high purity Fe-base alloys

The intergranular segregation of Sb and Ni in αFe was studied by scanning Auger electron spectroscopy in ultra-high purity FeSb and ternary Fe1% NiSb and Fe2% NiSb alloys. The segregation isotherms of Sb at 550°C are considerably steepened by Ni additions which also reduce the bulk Sb content at which the boundaries are saturated with Sb. For a given bulk Ni content, the Ni coverage increases linearly with the Sb coverage, in qualitative agreement with Darken and Simkovich's equations derived from the Gibbs adsorption isotherms. Better quantitative agreement is obtained with the regular solution model of co-segregation. The results appear consistent with a strong NiSb attractive interaction ( β NiSb gb ∼- 10 kJ·mole −1) and reveal the existence of a weaker but appreciable SbSb attraction ( β sb gb ∼- 5,4 kJ·mole −1).

Low resistance ohmic contacts containing Sb to GaP

A comparison has been made of the contact resistances of AuZn and AuZnSb alloyed contacts to p-type GaP and of AuGeNi and AuGeNiSb alloyed contacts to n-type GaP. The addition of antimony contact materials reduces the contact resistance and this reduction is greatest when the process of contacting is carried out at temperatures below 500°C.

Kalorimetrische untersuchungen an festen legierungen der systeme eisen—antimon, kobalt—antimon und nickel-antimon

In order to obtain the formation enthalpies of solid alloys in the FeSb, CoSb and NiSb systems a high-temperature calorimeter has been constructed. With this device, the solution enthalpies of the alloys and their components have been determined. The absolute values of the negative formation enthalpies which were calculated from the solution enthalpies increase within the series FeSb → CoSb → NiSb. The maximum values of the enthalpies of formation are: Δ H B = − 0.044 kJ g-at. −1 (at 57 at.−% Fe); Δ H B = − 27 kJ g-at. −1 (at 52 at.−% Co) and Δ H B = − 33 kJ g-at. −1 (at 51 at.−% Ni). These, for the most part highly negative, values are indicating that considerable non-metallic contributions to the bonding energies are existing in these systems. This leads to the formation of NiAs-phases in the central parts of the concentration ranges.

Atomic and magnetic structure of the Heusler alloys Ni2MnSb, Ni2MnSn, and Co2MnSn

Saturation magnetization, X-ray and neutron diffraction measurements were made on ferromagnetic alloys in the compositions Ni2MnSb, Ni2MnSn, and Co2MnSn. The compounds investigated have a crystallo-chemical structure of L21 type, with a partial disorder among NiSb atoms in the case of Ni2MnSb and Ni(Co)‒Mn atoms in that of Ni2MnSn and Co2MnSn. It was also found that in Heusler alloys the Ni atoms have zero magnetic moment, but the Co atom has a magnetic moment different from zero. The values of the magnetic moment of Mn and Co atoms were also calculated at 80 °K and found to be μMn = 3.60 to 3.75 μB, μCo = 0.7 μB. [Russian text ignored]

Contribution a l'etude des systemes NiSb et CoNiSb par diffraction-X

Some phases in the Ni-Sb system have been precised. The solid solution of antimony in nickel extends to 9.4 at. % Sb. The Ni 3Sb phase has an orthorhombic Cu 3Ti-type lattice with the following parameters: a = 5.317 A ̊ , b = 4.277 A ̊ et c = 4.519 A ̊ . The homogeneity range of the θ phase extends from Ni 7.2Sb 3 to Ni 6.9Sb 3. The study of the Co-Ni-Sb system for compositions with more than 50 at. % Sb (at 600°C), has allowed us to determine the (Co, Ni)Sb 3 solution limits: from 0 to 31 at. % Ni. The extent of the MeX 3 phase (X = P, As, Sb et Bi) can be correlated to the metallic character of the Me-X bonds. Whereas the CoSb 1.85 and NiSb 2 phases are almost mutually insoluble, the Co 1± xSb and Ni 1±xSb phases on the contrary form a continuous solid solution.

アミンアルカリ浴での陽極酸化と金属塩添加時の電解発色について

This paper describes integrally colored films which have been prepared by electrolytic coloring simultaneously with anodizing in aqueous solutions of ammonium hydroxide and ethylenediamine containing ammonium fluoride and metallic salts.When specimens were electrolyzed by AC in ammonium hydroxide bath [containing NH4OH 2.3mol, NH4F 0.27mol, NH4-tartrate 0.1mol, (NH4)2CO3 0.1mol, and Ni (Fe and Sb) salt 0.02mol] for 30min. under current density of 2Amp/dm2, a black or brown colored film(about 5μ in thickness) was obtained.The corrosion resistance of this film was higher than that of the anodized film in H2SO4, and its hardness decreassed by sealing with boiling water.On the other hand, when ethylenediamine solution [containing (NH2CH2)2 0.5-1%, NH4F 0.27mol, NH4-tartrate 0.05-0.3mol, (NH4)2CO3 0.05-0.2mol and Ni (Co, Sb, Fe, Ag, Cd, Zn, and Cu) salt 0.02mol] was used as an electrolyte under the same conditions of the above electrolysis, the following films were obtained:a black film for Ni and Sb saltsa brown film for Fe, Zn, Co, and Cd saltsa yellow film for Ag saltand a green film for Cu saltThe hardnesses and corrosion resistances of the colored films decreased and their colors faded after sealing with boiling water.

The influence of impurities on some properties of high purity magnesium

F. Sauerwald found that the grain refining occured with the addition of Zr to molten magnesium, and this grain refining effect of Zr was influenced by the alloying elements to Mg; those having unfavorable effect were the alloying elements such as Al, Si, Mn, Ni Sb etc.In this paper the effect of zirconium on the grain refinning of cast high purity magnesium containing Al, Si and Mn as impurities and the influences of Al, Si and Mn as impurities on grain refinement of cast Mg-Zn-Zr alloy were reported.Resualts obtained were as follows:1. In the case of high purity magnesium without other elements as impurities, the grain refining effect was favored by the addition of 0.5% Zr.2. The grain refinning effect was marked with the addition of Zr when small quantity of impuritiesexist.3. When the quantity of Zr was 3.5%, the allowable limit of impurities for grain refinement was about 0.5%Al, 0.05%Si and 0.02%Mn.4. Little prevcnting effect of impurities for grain refinement on Mg-Zn (3%)-Zr alloy was observed when the amount of Al, Si, and Mn was so small that they might be considered as impurities.