Showing papers in "Powder Metallurgy in 2017"
TL;DR: In this paper, a single-phase CoCrFeMnNi HEA was produced by powder metallurgy (PM) using gas atomised powder and selected PM methods are presented.
Abstract: Lately high-entropy alloys (HEAs) have been the topic of extensive research, as these materials are promising candidates for many challenging applications, as for example tools, moulds and functional coatings In contrast to conventional alloys, HEAs consist of five or more principal elements, each having a concentration between 5 and 35 at-% Against expectations, HEAs show a rather simple microstructure consisting preferentially of cubic phases Due to this microstructure, HEAs show promising properties, eg in terms of high-temperature stability, high strength and ductility Within this research, a single-phase CoCrFeMnNi HEA was produced by powder metallurgy (PM) In contrast to conventional metallurgy, PM offers a lot of advantages, eg good material efficiency and high shape complexity Gas atomised powder was used and selected PM methods are presented (eg pressureless sintering, spark plasma sintering, additive manufacturing (EBM)) The process methods were evaluated by characterising
68 citations
TL;DR: In this article, aluminium matrix hybrid composites (AMHCs) were fabricated by powder metallurgy and the effect of nano-microparticles on the performance of AMHCs was investigated.
Abstract: In this study, aluminium matrix hybrid composites (AMHCs) containing 10 wt-%SiC microparticles and x wt-%TiB2 (x = 1, 3 and 5) nanoparticles were fabricated by powder metallurgy. The effect of TiB...
49 citations
TL;DR: In this article, the microstructures and properties of the sintered alloys were compared using scanning electron microscope, X-ray diffraction, mechanical property testing and electrochemical testing.
Abstract: The AlFeCoNiCrTi high-entropy alloy (HEA) powders were prepared by high-energy ball milling. The ultrafine-grained WC–HEA and WC–Co-cemented carbides were fabricated through planetary ball milling and heat-pressure sintering. The microstructures and properties of the sintered alloys were compared using scanning electron microscope, X-ray diffraction, mechanical property testing and electrochemical testing. It has been shown that the AlFeCoNiCrTi HEA can be used as a binder for the ultrafine-grained WC-based cemented carbide. The WC–HEA-cemented carbide has better performances than the WC–Co-cemented carbide. The suitable contents of HEA can inhibit the WC grain growth and improve the mechanical properties and corrosion resistance of cemented carbides.
40 citations
TL;DR: In this paper, the results of XRD results and SEM observations confirm the formation of TiB whiskers as a result of the reaction between Ti and TiB2 particles, however, some unreacted TiB 2 particles have remained in the composite owing to the incomplete chemical reaction between matrix and additives.
Abstract: Titanium and titanium matrix composites, reinforced with TiB2 particles, have been synthesised by the spark plasma sintering method at 1050°C under 50 MPa pressure, using mixtures of 2.4 wt.-% TiB2 and 97.6 wt.-% Ti powders. The changes in microstructural features and mechanical properties were investigated. XRD results and SEM observations confirm the formation of TiB whiskers as a result of the reaction between Ti and TiB2. However, some unreacted TiB2 particles have remained in the composite owing to the incomplete chemical reaction between matrix and additives. The measured mechanical properties demonstrate that the increase in hardness and tensile strength with TiB2 addition is mainly attributed to the generation of TiB whiskers, increase in relative density and decrease in grain size, while the reduction in bending strength is possibly due to the plastic restraint imposed on the matrix by the TiB whiskers and unreacted TiB2 particles.
39 citations
TL;DR: In this paper, a methodology for the analysis of the surface chemistry of the Ti-powder by XPS utilising internal standard reference was developed, which was used for the surface analysis of titanium powder and identification of its surface oxide composition.
Abstract: Surface chemistry of the titanium powder has particularly growing interest due to the increasing application of titanium components prepared by powder metallurgy, in particular metal injection moulding and additive manufacturing. Due to the high chemical activity, number of titanium oxides, calcium and complex Ca–Ti–oxides can be expected on the component/medical implant surface, depending on powder and component manufacturing and post-treatment, but are very difficult to analyse due to the lack of the experimental data and analysis methodology. Therefore, a methodology for the analysis of the surface chemistry of the Ti-powder by XPS utilising internal standard reference was developed. The obtained methodology was used for the surface analysis of titanium powder and identification of its surface oxide composition. The results show that the powder surface is covered by TiO2 layer in the form of rutile with a thickness of 4.4 nm. Carbon and nitrogen impurities were also found present on the powder ...
35 citations
TL;DR: In this article, the fabrication of different weight percentages of (0.2 -2.5 ) nickel powder-filled aluminium alloy composites by stir casting techniques under a controlled environment is described.
Abstract: This research paper describes the fabrication of different weight percentages of (0–2 wt-%) nickel powder-filled aluminium alloy composites by stir casting techniques under a controlled environment...
35 citations
TL;DR: In this article, the annular geometry of the gas nozzle is changed to a convergent-divergent (CD) profile, which is capable of operating stably at low pressures of 0.8
Abstract: Additive manufacturing processes such as selective laser melting and electron beam melting require small particle sizes. A widely used technique to produce suitable powders is close-coupled atomisation. To further decrease the achieved particle sizes, the annular geometry of the gas nozzle is changed to a convergent–divergent (CD) profile. This novel configuration is capable of operating stably at low pressures of 0.8 MPa and above. Beyond that, the unwanted effects of lick-back are avoided. Different nozzles with conventional and convergent–divergent annular geometry have been designed based on fluid-flow calculations. The aspiration pressure was measured to determine stable process windows. Powders from a CuSn alloy were produced using cold and hot gas atomisation to show the influence on the process stability, particle size and morphology. High-speed recordings are used to investigate the process conditions of the different nozzle configurations.
34 citations
TL;DR: In this paper, a theory that explains the cause of process control agents (PCAs) induced contamination is presented, and an attempt is made through reviewing the literature to reason why there is ignorance.
Abstract: The top–down approach of mechanical ball milling/alloying is the most commonly adopted route towards materials development. It is however surprising that despite the large impact that it has, process induced contamination (particularly from process control agents (PCAs)), remains less studied and often ignored. In this article, a theory that explains the cause of PCA-induced contamination is postulated. An attempt is then made through reviewing the literature to reason why there is ignorance. Influence of contamination on material’s properties is then reviewed; revealing the dubious behaviour of contaminants. No first-hand experimental data are presented. The article is written with the interest and objective to create awareness on contamination, which remains highly under appreciated.
21 citations
TL;DR: Ceramic particle reinforcement can be used to improve the surface properties of Ti6Al4V (Ti64) alloy and powder metallurgy route is a promising method to fabricate such reinforced Ti64 components.
Abstract: Ceramic particle reinforcement can be used to improve the surface properties of Ti6Al4V (Ti64) alloy. Powder metallurgy route is a promising method to fabricate such reinforced Ti64 components. To ...
20 citations
TL;DR: In this paper, the chemistry including oxygen content of the powder was measured by inductively coupled plasma optical emission spectrometry and hot fusion and the morphology was evaluated by scanning electron microscope.
Abstract: Additive layer manufacturing (ALM) offers for production of parts and components for aeronautical applications potential cost benefits over conventional manufacturing routes. In particular, powder bed processes offer a high degree of design flexibility while enabling weight reduction due to topological optimisation. The quality and properties of the parts are strongly dependent on the powder quality which, in turn, is influenced by handling and storage of the powder. For this reasons an undefined contamination of atomised powder materials by oxygen and hydrogen has to be avoided. Aluminium-silicon powder was aged under atmosphere of different moistures and temperatures for defined duration. The effect of these environments as well as the effect of vacuum drying on the flowability was investigated. The morphology was evaluated by scanning electron microscope. The chemistry including oxygen content of the powder was measured by inductively coupled plasma optical emission spectrometry and hot fusion ...
13 citations
TL;DR: In this paper, the fabrication process of MHSs with optimum mechanical properties has been investigated, and the results indicate that samples that were sintered at the temperature of 1175°C for 4:30h resulted in superior mechanical and physical properties.
Abstract: Metallic hollow spheres (MHSs) are developed to be used in structural applications in syntactic and metal foams. These foams are lightweight and energy-absorbing structures which also can be used for acoustic insulation. In this study, the fabrication process of MHSs with optimum mechanical properties has been investigated. To achieve this goal, polystyrene spheres were coated with iron powder and an organic binder. During the multi-stage heat treatment, the green spheres were sintered into MHSs. Sintering was done at various temperatures (1125, 1150, 1175 and 1200°C) at different durations (3:30, 4:30 and 5:30 h). The influence of the different sintering durations and temperatures on mechanical features, microstructure and density was studied as well. The obtained results indicate that samples that were sintered at the temperature of 1175°C for 4:30 h resulted in superior mechanical and physical properties.
TL;DR: In this article, a quantitative X-ray-diffraction analysis of water atomised copper powders (AT-Cu) has been performed by continuous and interrupted mechanical milling (MM) for different milling times.
Abstract: Water atomised copper powders (AT-Cu) have been processed by continuous and interrupted mechanical milling (MM) for different milling times. For continuous cycle the powders are subjected first to a severe flattening process and then to an intense welding phenomenon. In the case of interrupted cycle MM behaviour proceeds with an intense fracturing process. By quantitative X-ray-diffraction analysis the interrupted cycle shows constantly a delay of the microstructure evolution with all the phenomena shifted at longer milling time. For both types of cycle crystalline size decreases down to 20 nm. After 6000 min of interrupted MM the formation of Cu2O has been revealed and a strong dependency between oxygen content and microstructural parameter has been attested analysing the variations of lattice parameter and lattice strain. When the interstitial oxygen atoms lose their Cottrell locking action dislocation annihilation occurs leading to a reduction of dislocation density and lattice strain.
TL;DR: In this article, the effects of particle size on the densification were analyzed in many respects including shrinkage, strain rate, apparent activation energy, and work of sintering.
Abstract: Densification behaviours of 17-4PH stainless steel powders (SUS17-4PH) of three different particle sizes during the sintering were investigated. The samples with different mean particle sizes of 3.17, 4.22 and 8.30 µm were prepared through powder-binder mixing, injection moulding, and solvent and thermal debindings. The in situ shrinkage data measured by dilatometry tests were treated to analyse the densification behaviour of each sample. In order to characterise the densification behaviour with a minimum set of experiments, the master sintering curve (MSC), as well-known and straight-forward approach, was employed. After constructing the MSCs for powders of different particle sizes, the effects of particle size on the densification were analysed in many respects including shrinkage, strain rate, apparent activation energy, and work of sintering.
TL;DR: In this paper, two types of copper base alloys, i.e., Cu-9Sn-8Pb and Cu-28Zn, were investigated for sintering in the range of 890-970°C for 20 min.
Abstract: The compacting pressure is one of the key parameters which affects sintering phenomena, such as fragmentation, rearrangement and densification. However, the type of alloy also has a similar significance which should be considered. To demonstrate the effect of the mentioned parameters, two types of copper base alloys, i.e. Cu–9Sn–8Pb and Cu–28Zn, were investigated in the present study. Prealloyed powders were compacted at 100 and 400 MPa, respectively, and sintered in the range of 890–970°C for 20 min. In situ images of the samples were taken at various sintering conditions, and the shapes were recorded. For both materials, in case of compaction at lower pressure, the gravity-induced distortion known as ‘elephant foot’ phenomenon was not observed, and the specimens show shape retention during sintering even at higher temperatures, while samples compacted at 400 MPa showed different responses to the sintering conditions: A-shaped distortion (elephant foot) occurred in the bronze alloy, while in the ...
TL;DR: In this article, the effect of milling time on wear behavior of the Ti6Al4V alloy produced with the high-energy milling method was investigated, and wear tests were performed using a pin-on-disc type wear testing device, under three different loads at four different sliding distances in simulated body fluid environment.
Abstract: In this study, the effect of milling time on wear behaviour of the Ti6Al4V alloy produced with the high-energy milling method was investigated. The Ti6Al4V alloy was milled at five different milling times in a mechanical alloying device. The milled powders were cold-pressed under 620 MPa pressure, sintered at 1300°C for 2 h and cooled to room temperature in the furnace. The sintered alloys were characterised with SEM, XRD and hardness and density measurements. Wear tests were performed using a pin-on-disc type wear testing device, under three different loads, at four different sliding distances in simulated body fluid environment. Results showed a decreasing powder size with increasing milling time. The highest decline in size occurred for the powders milled for 120 min. The result of hardness measurements and wear tests showed that samples milled for 120 min had both the highest hardness value and the lowest weight loss.
TL;DR: In this article, a systematic characterisation of the boundary structure in WC-Co cemented carbides was made as a function of the cobalt content and carbon potential using electron backscattered diffraction technique, with the aim to analyse the mechanisms of WC/Co phase boundary and WC/WC grain boundary development.
Abstract: A systematic characterisation of the boundary structure in WC-Co cemented carbides was made as a function of the cobalt content and carbon potential using electron backscattered diffraction technique, with the aim to analyse the mechanisms of WC/Co phase boundary and WC/WC grain boundary development. The fraction of grain boundaries with basal or prismatic habit planes was estimated using a stereological method. Special grain boundaries were classified as a function of the rotation axis between adjacent grains. Although a few special grain boundaries originate from the powder, most grain boundaries form during heat treatment. The development of grain boundaries and phase boundaries during sintering is discussed from the results. The surprising lack of variation in the distribution of boundary types over large changes in volume fraction and composition is particularly commented. Finally, a mechanism of cooperative migration of grain boundaries and phase boundaries is proposed to explain microstruct...
TL;DR: In this article, the effect of the sintering conditions on both mechanical and magnetic properties of the soft magnetic alloys processed by metal injection molding was evaluated, and the authors determined the influence of the Sintering parameters on the final properties of two alloys were sintered under different conditions.
Abstract: Soft magnetic materials are used in a wide variety of electromagnetic devices such as motors, relays and sensors. Over the years, the devices are becoming smaller. Therefore, it is essential to produce small parts without compromising the final properties. Metal injection moulding (MIM) is a cost-effective technique to produce small and complex soft magnetic parts with optimal mechanical and magnetic performance. These properties can be improved by maximising the sintered density and by the reduction of impurities content. These factors are strongly related to the sintering parameters. The goal of this study is to determine the influence of the sintering parameters on the final properties of iron–silicon soft magnetic alloys processed by metal injection moulding. In this work, two alloys were sintered under different conditions. The effect of the sintering conditions on both mechanical and magnetic properties was evaluated.This paper is part of a special issue on the Advances in Materials and Proc...
TL;DR: In this article, the authors summarise studies with different approaches to limit carbide precipitation in a Ti-22wt-%Nb alloy processed by metal injection molding (MIM) processing and reveal the role of the elemental additions and analyse the structure of the different carbides formed.
Abstract: During metal injection moulding (MIM) processing, titanium tends to react with carbon from the polymeric binder. Thus, carbides, which can effect embrittlement, might be formed if the carbon solubility of the alloy is exceeded. Especially in β-titanium alloys, this is a critical issue, because β-phase stabilising elements like V, Mo and Nb decrease the carbon solubility of the Ti-matrix. This study summarises studies with different approaches to limit carbide precipitation in a Ti–22wt-%Nb alloy processed by MIM. Adding Zr led to a significant reduction in the amount and size of carbides due to an increase in the lattice constant. Furthermore, boron was added supporting a finer distribution of the carbides. Scanning electron microscopy and transmission electron microscopy investigations reveal the role of the elemental additions and analyse the structure of the different carbides formed. Combinations with heat treatments led to significant reduction in the amount of carbides.
TL;DR: In this article, the authors compared the COPGLOW (compacted powder glow discharge analysis) method to the more established XPS (X-ray photoelectron spectroscopy) technique, in terms of similarity in reported elemental contents.
Abstract: The purpose of this paper is to compare, in terms of depth composition profile, a recycled hastelloy X powder and a virgin powder of the same alloy. We compare also the COPGLOW (compacted powder glow discharge analysis) method to the more established XPS (X-ray photoelectron spectroscopy) technique, in terms of similarity in reported elemental contents. A good match between the two methods was obtained on the surface of the powder particles (using an etching depth of 1 nm). Similar oxide layer thickness, of about 0.5–1 nm, was found on both powders by COPGLOW. Oxidation sensitive elements, such as Cr, were found on the surfaces by both XPS and COPGLOW on both powders. Surface content of Si appears to have decreased during use in selective laser melting. Finally, the two methods did not otherwise reveal any unexpected features in the depth profiles.
TL;DR: In this paper, the effects of chromium carbide on the microstructures and wear resistance of high speed steel were studied using X-ray diffraction characterisation and EDS analysis.
Abstract: The effects of chromium carbide on the microstructures and wear resistance of high speed steel were studied. Metal matrix composites (MMCs), based on M2 high speed steel reinforced with different percentages of Cr3C2, were produced following a metal injection moulding route: feedstock manufacturing, injection, debinding and sintering. The weight fraction of hard second phase particles in tool steels is limited by the formation of large interconnected carbides that embrittle the alloy. Additions of up to 14 wt-% Cr3C2 were successfully prepared. The influence of the chromium carbide content on the optimum sintering temperature was analysed. The mechanical properties of the sintered composites were obtained by measuring hardness and wear behaviour. Microstructure and wear mechanisms were investigated by means of scanning electron microscopic observations. These results, together with X-ray diffraction characterisation and EDS analysis, allow explanation of the mechanisms responsible for the wear beh...
TL;DR: In this article, the authors used finite element models to predict deformation and densification behavior of nickel-based superalloys during hot isostatic pressing, which can be used to reduce the cost and time of trial and error.
Abstract: Hot isostatic pressing of nickel-based superalloys has important applications for manufacturing near-net shape parts such as turbine disks and jet engine parts, which have to operate at high temperatures. Finite element modelling can be used to predict deformation and densification behaviour of such superalloys. Thus, the cost and time of trial and error to obtain the required geometry of the part can be reduced, such that near-net shape parts can be manufactured more economically. Numerical simulations were carried out by implementing the model of ElRakayby and Kim into Abaqus-FEA. The model parameters (relative density functions f and c) for the nickel-based superalloy were obtained from the creep response and compressive strength of porous and solid powder compacts at high a temperature. The agreement between finite element calculations and the experimental data was good for densification, shape change and density distribution of nickel-based superalloy during hot isostatic pressing.
TL;DR: In this paper, the impact of HIP pressure on phase transformation time dependency was investigated using grid method on SEM images, and the authors found significant influence of pressure on hardenability.
Abstract: The new HIP cooling systems enable very fast cooling rates under isostatic pressure. This does not only enable shorter HIP cycles but also allows complete heat treatment cycles to be performed in one HIP cycle. It has been shown in previous studies that extreme pressures of several thousand bar can push phase transformation towards longer times. The new URQ HIP cooling systems give the opportunity to investigate the impact of pressures up to 2000 bar on phase transformation time dependency. For each of the two materials in this study, a comparison of austenite phase transformation time at 100 and 1700 bar was performed. The study was performed by isothermal heat treatment of specimens for a specific time followed by quenching. To evaluate the influence of pressure on hardenability, the phase fractions were evaluated using grid method on SEM images. The study found significant influence of HIP pressure on hardenability.
TL;DR: In this article, the influence of different alloying additions either as elemental powders (Cr, Mn, Si) or as maste... has been applied in a systematic study.
Abstract: Sintering of steels containing oxidation-sensitive elements such as Cr, Mn and Si is a big challenge for the powder metallurgy (PM) industry but also a chance that could open the door to a new variety of compositions, properties and prices. However, even when very small amounts of these elements are mixed with an iron base powder, the chemical reactions taking place during sintering can be changed significantly. Application of high purity sintering atmospheres is not sufficient to avoid the formation of stable oxides on the surface of the alloying particles, since the source of oxygen can be – and in general is – the base powder itself. This is because the gaseous reaction products from the reduction of the oxides covering the base powder particles act as oxidising agents for elements with higher oxygen affinity. In this study, thermoanalytical techniques have been applied in a systematic study about the influence of different alloying additions either as elemental powders (Cr, Mn, Si) or as maste...
TL;DR: In this article, the effects of microwave sintering (MWS) on microstructural, tribological and corrosion properties of Cu0.7Ni0.3-5.5% Al2O3 nanocomposites were evaluated.
Abstract: In the present study, the effects of microwave sintering (MWS) on microstructural, tribological and corrosion properties of Cu0.7Ni0.3-5 wt-% Al2O3 nanocomposites were evaluated. The Cu and Ni powders along with Al2O3 nanopowder were mixed in a high-energy ball mill. The XRD patterns indicating formation of Cu0.7Ni0.3 solid solution alloy during mechanical alloying process. The mechanically alloyed powders were compacted by coldpress, and sintered samples at 200 and 300°C for 30 and 60 min by means of conventional sintering and MWS. Tribological properties of sintered samples were evaluated by ball-on-disk wear test. For MWS, results indicate that increasing the MWS temperature decreased the wear rate about 30%. Corrosion behaviour of nanocomposites were studied by cyclic potentiodynamic polarisation in 1 M NaOH solution and was found that corrosion current density of microwave sintered sample was decreased almost 35 times of that for conventional sintered sample.
TL;DR: In this paper, the effect of the sinter-hardening treatment in improving the tooth root fatigue resistance of gears obtained by powder metallurgy was investigated, and the results showed that the effect was negligible.
Abstract: The present paper is aimed at investigating the effect of the sinter-hardening treatment in improving the tooth root fatigue resistance of gears obtained by Powder Metallurgy. The gears were produc...
TL;DR: In this article, the rate dependence of hardmetal powder pressing in cutting insert production is investigated experimentally and numerically and the results indicate that rate-dependent frictional effects are the dominating feature and accordingly, it can be argued that for the metal powders investigated here, creep deformations do not have to be accounted for in the constitutive description at the timescales relevant for powder pressing and when the shape after sintering is concerned.
Abstract: The rate-dependence of hardmetal powder pressing in cutting insert production is investigated experimentally and numerically. In the latter case, the finite element method is relied upon using a continuum mechanics approach. In particular, possible rate-dependency due to creep deformation and rate-dependent friction is discussed with the experimental investigation focusing mainly on dimensional changes during sintering but also pressing forces. The results indicate that rate-dependent frictional effects are the dominating feature and accordingly, it can be argued that for the metal powders investigated here, creep deformations do not have to be accounted for in the constitutive description at the timescales relevant for powder pressing and when the shape after sintering is concerned. For the present powder, the apparent frictional effect decreases at higher pressing rates. Additional details of the friction behavior are studied comparing finite element simulations with experiments.
TL;DR: In this paper, an attempt is made to identify flowability indicators which can describe the flow performance of the powder during the powder layering (i.e. recoating) step; common to all powder bed fusion processes.
Abstract: In powder bed fusion additive processes the flow properties of the powder influence the quality of the final component and the efficiency of the process. In this investigation an attempt is made to identify flowability indicators which can describe the flow performance of the powder during the powder layering (i.e. recoating) step; common to all powder bed fusion processes. To this end, shear tests were performed by means of a powder rheometer. Bulk density, flow function and degree of cohesion were measured. The results suggest that there is a good correlation between the aforementioned parameters and the flowability of the powder during SLM processing. In addition, it was found that thermal treatments and tumbling enhance flowability. Thermal treatments were performed at 150, 200 and 250°C for a period of 10 min and in air.
TL;DR: In this paper, the effect of the starting alloy powder size on the morphology of composite powder was studied and the spray-drying process was selected to agglomerate ball milled NiCoCrAlY-Al2O3 composite powders.
Abstract: Spray-drying process was selected to agglomerate ball milled NiCoCrAlY–Al2O3 composite powders. The effect of the starting alloy powder size on the morphology of composite powder was studied. The p...
TL;DR: In this paper, a model was developed to predict the high temperature flow behavior of the Cu-28Zn pre-alloyed powder compact, and the results indicated that the strain-dependent constitutive equations are in good conformity with the experimental results.
Abstract: In the field of the deformation process modelling, constitutive equations tend to be utilised as a calculation basis for the estimation of the materials’ flow responses. This holds also for powder metallurgy products. Hence, in this study, the flow behaviour of sintered Cu–28Zn pre-alloyed powder compacts was investigated by a collection of isothermal hot compression tests in the temperature range of 550–850°C at strain rates of 0.001, 0.01, 0.1 and 0.5 s−1 up to the true strain of 0.6. For the sintered part with a predefined porosity of 9.4%, the impacts of the temperature and strain rate on the deformation behaviour were shown by the Zener–Hollomon parameter in an exponent-type equation. As a result, a model was developed to predict the high temperature flow behaviour of the Cu–28Zn pre-alloyed powder compact. The results indicated that the strain-dependent constitutive equations are in good conformity with the experimental results.
TL;DR: In this article, a novel method to synthesize sub-micron FeWB powders is proposed, by which pure-phase FeWB powderers with a particle size of ∼500 nm were successfully obtained.
Abstract: A novel method to synthesise sub-micron FeWB powders is proposed, by which pure-phase FeWB powders with a particle size of ∼500 nm were successfully obtained. This method consists of three steps: water atomisation, annealing treatment and acid dissolution of the matrix. Systematic characterisation was carried out throughout the preparing process to determine the detail phase evolution, chemistry features as well as the changes in particle size. It was found out that the as-atomised powders consisted of only α-Fe solid solution where W and B atoms are dissolved as solute atoms. And the annealing treatment could facilitate the precipitation of W and B atoms from the matrix to form tiny dispersive continuous net-like precipitates. Analyses showed that Fe6W6C, Fe3W3C and FeWB were precipitated in sequence during the annealing process. And following the chemical treatment, the α-Fe matrix and surface oxide layers could be completely removed and FeWB powders could be successfully recovered.