Iron-nickel Powders Research Articles

Electrochemical processing of heavy tungsten alloy wastes for obtaining a microdispersed iron-nickel base powder by using alternating current

Electrochemical processing of heavy tungsten alloy wastes (wt.%: W 78,8, Ni 15,2, Fe 6,0) under the cyclic using of direct and alternating current in ammonia-alkaline solutions has been investigated. High dissolution rate of alloy wastes, as well as degree of tungsten extraction, has been provided. The electrochemical process has been accompanied by production of microdispersed iron-nickel powder, that contains up to 2 wt.% tungsten.

Manipulating Chladni Patterns of Ferromagnetic Materials by an External Magnetic Field

Ernst Chladni is called the father of acoustics for his work, which includes investigating patterns formed by vibrating plates. Understanding these patterns helps research involving standing waves and other harmonic behaviors, including studies of single electron orbits in atoms. Our experiment vibrates circular plates which result in well-known patterns. Alternatively to traditional experiments that used sand or salt, we use magnetic materials, namely iron filings and nickel powder. We then manipulate the patterns by applying a localized external magnetic field to one of the rings that moves a segment of the magnetic material in that ring to the next inner ring. The results show a significant decrease in magnetic field necessary to move the magnetic material at higher frequencies as well as a significant decrease in the magnetic field required to move the magnetic material as nickel powder is substituted for iron filings while keeping the mass constant.

Study of the effect of dispersion and homogeneity of the structure on the properties of powder metastable austenitic carbide steels and diamond tools

Diffusion and homogenization in powder systems of varying degrees of dispersion «iron (5 μm) – nickel (5 μm or 50 nm)» during sintering (900 and 1000 °C), as well as spark plasma sintering using the Matano-Boltzmann method were studied. In these systems, the calculated diffusion coefficients in pairs of micron powders, sintered without application of pressure (900 °C, 6 h) and the spark plasma method (900 °C, 5 min), were equal to 7·10–10 cm2/s. It is shown that in diffusion pairs based on microdispersed iron powder, the use of nanodispersed nickel powder instead of microdispersed one contributes to an increase in the diffusion coefficient at a temperature of 900 °C by a factor of 2. The constants in the sintering kinetics equation of V.A. Ivensen are calculated for iron–nickel powder systems. Through them the factors activating the sintering of these systems were established. The dependences of the structure-phase composition and physicomechanical properties of carbides of the Fe (base) system — 14 wt.% Ni – 8 wt.% TiC system on the sintering temperature in the interval t = 900÷1200 °C, dispersion and homogeneity of the structure were determined. The dependences of grain size, porosity, hardness, microhardness, toughness, bending strength on sintering temperature are shown. The established dependences of the tribotechnical properties on the degree of homogeneity of the solid solution and the volume of the phase transformation of the metastable austenite to deformation martensite during friction on the abrasive were similar for carbide steels and diamond tools based on carbide steels. The optimal values of the coefficient of variation of nickel concentration in austenite in carbidostils of the same chemical composition, but different dispersion, providing the maximum amount of austenite decomposition and high values of the diamond tool grinding coefficient were 5 in both systems, but the sintering parameters differed. It is shown that the physicomechanical properties of the studied systems depend on the porosity and dispersion of the structure, and the tribotechnical properties are subjected to the homogeneity of the structure of the steel.

An approach to nickel ferrite synthesis

In this letter, a new approach to the synthesis of nickel ferrite has been performed. Nickel ferrite nanoparticles have been prepared via a straightforward method by simply heating iron-nickel tertracyanide powder (FeNi(CN)4·3H2O) in air at 400 °C for only 5 min. During the heating process, it was observed that iron-nickel cyanide powder ignites at a certain point in the material and then this ignition propagates in a wave-like manner through the rest of the mass. As the ignition front propagated through the material, an extreme expansion occurred in a way similar to musical accordion and eventually formed nickel ferrite nanoparticles. Samples were characterized using XRD, SEM, HRTEM, TGA and Raman spectroscopy. All analysis confirmed the successful formation of single phase nickel ferrite. The present method can be extended to synthesize other ferrites. The presented approach is characterized by both simplicity and scalability which makes it promising for industrial utilization.

Treatment of Al Doura Oil Refinery Wastewater Turbidity using Magnetic Flocculation

The use of conventional flocculants such as Aluminum sulphate (Alum) alone to treat the wastewater may be insufficient to get the required turbidity, suspended solids removal as well as it requires relatively a long residence time. Magnetic flocculation is one of the used techniques for increase the efficiency of the turbidity removal. In the present study, three sets of experiments are carried out in order to investigate the possibility of increasing the suspended solid removal efficiency from Al Doura oil refinery wastewater using iron oxide (Fe3O4), Nickel (Ni), and Cobalt (Co) ferromagnetic powders with alum. The following operating conditions namely, pH, alum dose, ferromagnetic powder dose, and initial turbidity are studied. The results revealed that an improvement in turbidity removal efficiency is satisfied, as well as, a reasonable reduction in the sedimentation period is achieved. The highest turbidity removal is 99.88% that obtained for 122NTU sample for alum dose 120 mg/L+ Nickel dose of 80mg/L and pH of 6.5.

Treatment of Al Doura Oil Refinery Wastewater Turbidity using Magnetic Flocculation

The use of conventional flocculants such as Aluminum sulphate (Alum) alone to treat the wastewater may be insufficient to get the required turbidity, suspended solids removal. It also requires relatively a long residence time. Magnetic flocculation is one of the techniques used for increasing the efficiency of the turbidity removal. In the present study, three sets of experiments are carried out in order to investigate the possibility of increasing the suspended solid removal efficiency from Al Doura oil refinery wastewater using iron oxide (Fe3O4), Nickel (Ni), and Cobalt (Co) ferromagnetic powders with alum. The following operating conditions namely, pH, alum dose, ferromagnetic powder dose, and initial turbidity are studied. The results revealed that an improvement in turbidity removal efficiency is satisfied, as well as, a reasonable reduction in the sedimentation period is achieved. The highest turbidity removal is 99.88% that obtained for 122NTU sample for alum dose 120 mg/L+ Nickel dose of 80mg/L and pH of 6.5.

MECHANICAL ALLOYING WITH PARTIAL AMORPHIZATION OF FE–CR–CO–NI–MN MULTICOMPONENT POWDER MIXTURE AND ITS SPARK PLASMA SINTERING FOR COMPACT HIGH-ENTROPY MATERIAL PRODUCTION

This paper presents the results of studying the mechanical alloying (MA) effect on the surface morphology, microstructure and atomic-crystal structure of multicomponent Fe–Cr–Co–Ni–Mn powder mixture particles. The following materials were used as initial components: radio-engineering carbonyl iron powder (R-10 with an average particle size d = 3,5 μm), nickel powder (NPE-1, d = 150 μm), cobalt powder (PK-1u, d <71 μm), chromium powder (PH-1М, d <125 μm) and manganese powder (MR0, d <400 μm) were used. MA of the prepared mixture was carried out in the AGO-2 water-cooled mechanical activator using 9 mm steel balls with an acceleration of 90 g in air. Alloying time varied between 5 and 90 minutes. The ratio of ball mass to the mass of the mixture was 20 : 1. X-ray patterns of the initial and alloyed mixtures and the sample obtained by sintering were made on the DRON 3M diffractometer on FeKα radiation in the range of angles 2θ = 30°÷100°. The particle microstructure of the mixtures and compact sample section after sintering was studied by scanning electron microscopy. It is found that no peaks of the initial components are present on the X-ray pattern of the mixture after 90 minutes of mechanical activation, but there are peaks corresponding to the γ-Fe-based solid solution phase having a face-centered crystal lattice with an amorphous phase content increased by 20 %. A compact single-phase material was obtained by spark plasma sintering at 800 °С for 10 minutes from the mixture after 90-minute alloying. Material density was 7,49 kg/cm3, specific electrical resistivity was 0,94÷0,96·10–6 ·m, microhardness was 306÷328 kg/mm2, and the phase was distributed uniformly throughout the volume.

Study of Diffusion, Kinetics of Sintering, Structure and Properties in Powder Steels with Free and Spark Plasma Sintering

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Sintered Fe50Ni Alloy Produced by Mixing Iron and Nickel Powders

Fe50Ni alloys are used when very high magnetic permeabilities are necessary. Parts of these alloys can be produce by different mechanical processes. Metallurgical processes as investment casting and powder metallurgy can also be used. Sintered Fe50Ni parts have two disadvantages, in terms of magnetic properties: the presence of porosity and the limited grain size. This paper investigates the effects of compactation pressure on the final microstructure and density. Mixtures of atomized iron and carbonyl nickel powder were uniaxially pressed. Cylindrical samples with around 6.5g/cm3 of green density were vacuum sintered at 1220 °C. After sintering samples were cold deformed and then heat treated.

Coupling the dechlorination of aqueous 4-CP with the mechanochemical destruction of solid PCNB using Fe–Ni–SiO2

A novel combined process was developed for mechanochemical destruction of pentachloronitrobenzene (PCNB) in solid waste, coupled with the dechlorination of aqueous 4-chlorophenol (4-CP) using the nonhazardous residue from the solid-phase destruction step. Using the mixture of iron powder, nickel powder and quartz sand as the additives in a planetary ball mill under the room temperature, the mechanochemical reaction was induced and a complete destruction of PCNB was realized. The resulting solid residue was characterized by various measures including X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDS), which suggested that main components were carbon, chloride besides excess additives. Such nonhazardous residue was then used to effectively dechlorinate aqueous 4-CP. The residue achieving over 93% dechlorination rate was selected as the optimized content. With a series of verification experiments, a possible dechlorination mechanism was proposed, involving the reactions occurred on three interfaces (i.e. Fe/Ni, Fe/C and Fe/C/Ni).

Preparation of ultra-fine fibrous Fe–Ni alloy powder by coordinated co-precipitation–direct reduction process

The precursor prepared by coordinated co-precipitation was direct reduced by hydrogen to ultra-fine fibrous Fe–Ni alloy powder. The effects of concentrations of reactants, pH value, reaction temperature and additive on the preparation of precursor were systematically investigated. The structures, thermal decomposition processes and morphologies of the precursors were characterized by X-ray diffraction (XRD), thermal gravity-differential thermal analysis (TG-DTA) and scanning electron microscoy (SEM). The results show that using 2% polyvinylpyrrolidone (PVP) (in mass fraction) as additive, a well-dispersed precursor with a uniform morphology can be obtained in a solution with Fe2+ and Ni2+ total concentration (1:1) of 0.8 mol/L, pH value of 6.2 at 60 °C, and a pure and well dispersed fibrous iron-nickel powder can be prepared by direct reduction of this precursor in a mixed atmosphere of nitrogen and hydrogen at the temperature of 420 °C.

Corrosion-electrochemical behavior of composite layers produced by laser sintering of nanoscale iron-nickel powders

Corrosion-electrochemical behavior of composite layers formed by high-speed laser sintering of nanoscale Fe-Ni powders (3.2 and 10 wt % Ni) is studied with the use of anodic potentiodynamic curves recorded in a borate buffer solution in a neutral environment. Composite layers produced are shown to retain nanostructure properties of the original iron and nickel powders. The layers formed exhibit better passivation properties than do iron and nickel separately. Changes in the composition and properties of the surface layers formed by laser sintering before and after corrosion studies are confirmed by X-ray diffraction and X-ray photoelectron analyses.

Dynamics of finely dispersed inclusions, mass transfer, and phase formation in a compression plasma

The formation of nanoscale spherical clusters using finely dispersed iron-nickel powder injected into a compression plasma is investigated experimentally. The particle size distributions obtained in the experiment are statistically processed. The growth of an individual cluster is simulated taking into account the force interaction between the metal atom and the substrate surface.

Physical, Technological, and Magnetic Properties of Powder Iron-Nickel Alloys

Methods for the production of 36N, 78N, and 79NM iron-nickel powders have been investigated along with the technological and physical and chemical properties of those powders. Coreduction of the initial oxides was shown to be the most simple, cost-effective, and accessible method.

Load bearing capacity of bronze, iron and iron–nickel powder composites containing fullerene-like WS 2 nanoparticles

In the past few years, inorganic fullerene-like (e.g. IF) supramolecules of metal dichalcogenide MX 2 (M=Mo,W, etc.; X=S, Se), materials with structures closely related to (nested) carbon fullerenes and nanotubes have been synthesized. Recent experiments showed that IF possess lubricating properties superior to those of commercially available layered solid lubricant (2H–WS 2 polytype) in a wide range of operating conditions. It was shown before that the impregnation of a small amount of such nanoparticles into porous bronze matrix largely improve the tribological properties of bronze–steel contact pairs. In the present work, the effect of the PV (pressure–velocity) parameter on the transition to seizure for powdered bronze–graphite, iron–graphite and iron–nickel–graphite composites impregnated 2H and IF lubricant has been studied. The tribological tests were performed using a ring–block tester at loads of 150–1200 N and sliding speeds from 0.5 to 1.7 m/s. It was found that impregnation of IF into the pores improves the tribological properties of the powdered composites in comparison to 2H–WS 2 solid lubricant. Furthermore, it was established that the impregnation of oil together with the IF nanoparticles allows to provide very high load bearing capacity of the powdered materials. It is suggested that the transition to seizure occurs when the wear debrises accumulate in the pores on the surface. This process practically blocks the surface pores and limits the supply of the solid lubricant particles to the contact surface. The main advantage of the IF nanoparticles is attributed to: (a) slow release and supply of nanoparticles from the open pores to the surface; (b) sliding/rolling of the IF between the rubbing surfaces; and (c) prevention of the accumulation of the agglomerated wear particles in the pores. The model of third body was used in order to explain the effect of the wear particles, oil and solid lubricant particles on the friction and wear behavior of powdered composites.

Influence of the electrolysis temperature on the formation, composition, structure, and magnetic properties of highly dispersed iron and iron-nickel alloy powders

The influence of the electrolysis temperature on the formation, chemical and phase composition, structure, and magnetic properties of highly dispersed iron and iron-nickel (50∶50) powders is investigated. The optimal thermal conditions are determined for the production of powders with micron-sized particles in a two-layer electrolytic bath from concentrated solutions of electrolytes.

Sintering of elemental carbonyl iron and carbonyl nickel powder mixtures

Iron-nickel alloys with compositions ranging from pure iron to pure nickel at increments of 10 wt% have been prepared by mixing fine elemental carbonyl iron and nickel powders, and sintering at temperatures between 1200–1350°C. The addition of nickel to iron promoted densification and avoided abnormal grain growth at low concentrations. However the densification was retarded when the iron and nickel had approximately equivalent concentrations. As the concentration of nickel increased, the room temperature structures of the alloys gradually changed from α-Fe into γ-(Fe, Ni), with Fe-30 wt% Ni and Fe-40 wt%, Ni containing both phases. The relative abundance of each phase was determined by the degree of compositional homogeneity achieved in sintering.

射出成形を利用したＦｅ‐Ｎｉ合金焼結体の機械的性質に及ぼす脱バインダ条件の影響

The effect of debinding temperatures on mechanical properties of sintered Fe-4%Ni alloy compacts made by injection molding has been studied. Specimens were made of carboyl iron and carbonyl nickel powder having average diameters of 5 and 2 μm respectively. After specimens were debound in temperature range from 503K to 553K with a holding period of 7.2ks in the air, they were sintered at a constant temperature of 1523K with a holding period of 7.2ks in the reduced pressure of 1Pa. In the case of debinding in the air, there is the critical debinding temperature at which oxide particles begin to form. Above the critical debinding temperature, oxide particles precipitate along grain boundaries and within grains. As the debinding temperature becomes higher, they grow mainly along grain boundaries. The mechanical properties of sintered compacts change drastically above the critical debinding temperature. The tensile strength of the compacts debound above the critical temperature, for instance, takes maximum value and its elongation is drastically lowered.

Acute Oral Toxicity Study in Rats with Iron Nickel Powder

Acute Oral Toxicity Study in Rats with Iron Nickel Powder

Structure and properties of iron-nickel powder metallurgy alloys

Structure and properties of iron-nickel powder metallurgy alloys