Fine Copper Powders Production

2021 ◽  
Vol 410 ◽  
pp. 418-424
Author(s):  
Natalia E. Agarova ◽  
Lyubov M. Yakovleva ◽  
Roman S. Voinkov ◽  
Konstantin L. Timofeev
Keyword(s):  
Average Particle Size ◽  
Chloride Ions ◽  
Average Particle ◽  
Air Classification ◽  
Operating Modes ◽  
Electrolytic Copper Powder ◽  
Copper Powders ◽  
Powder Particles ◽  
Fine Copper

The article is devoted to the description of a method for producing electrolytic copper powder with an average particle size of 3 to 10 μm. In order to increase the proportion of the finely dispersed fraction during the electrolysis process, the composition of the electrolyte was changed. In particular, the content of chloride ions was increased from 6 to 53 mg/dm3. After the growth of the powder in industrial baths, its subsequent drying and sieving on vibrating screens, samples were obtained with a fraction of 5 μm content in the range from 3 to 38 %. Additionally, air classification of powders was carried out at various speeds of the classifier rotor from 800 to 2000 rpm. Based on the results of the study, the optimal ranges of the specific surface area and the size of the initial powder particles before classification, as well as the composition of the electrolyte and the operating modes of the classifier, were determined.

scholarly journals Characterization of dispersion strengthened copper with 3wt%Al2O3 by mechanical alloying

2004 ◽  
Vol 36 (3) ◽  
pp. 205-211 ◽  
Author(s):  
Viseslava Rajkovic ◽  
Olivera Eric ◽  
Dusan Bozic ◽  
M. Mitkov ◽  
Endre Romhanji
Keyword(s):  
Mechanical Alloying ◽  
Structural Changes ◽  
Early Stage ◽  
Structure Refinement ◽  
Average Particle Size ◽  
Copper Matrix ◽  
Alumina Powder ◽  
Average Particle ◽  
Micro Hardness ◽  
Electrolytic Copper Powder

The copper matrix has been dispersion strengthened with 3wt.%Al2O3 by mechanical alloying. Commercial alumina powder with an average particle size of 0.75mm was used for alloying. The mechanical alloying process was performed in a planetary ball mill up to 20h in air. After milling all powders were treated in H2 at 4000C for 1h, and finally hot pressing was used for compaction (800oC, 3h, Ar). Structure observations revealed a lamellar structure (Al2O3 particles largely restricted to interlamellar planes between adjacent copper lamellae) accompanied also by structure refinement. These structural changes were mostly completed in the early stage of milling, and retained after compaction. Micro hardness was found to progressively increase with milling time. So, after 5h of milling the micro hardness of the Cu+3twt%Al2O3 compact was 1540MPa, i.e. 2.5 times greater than for the as-received electrolytic copper powder (638MPa) compacted under identical conditions, while after 20h of milling it was 2370 MPa. However after exposing the tested compact at 800oC up to 5h, the achieved hardening effect vanished.

Investigating the Structure and Properties of the AlSi10Mg Alloy Manufactured by Means of Selective Laser Melting

2020 ◽  
pp. 71-85
Author(s):  
A.K. Karavaev ◽  
Yu.A. Puchkov
Keyword(s):  
Particle Size ◽  
Heat Affected Zone ◽  
Average Particle Size ◽  
Average Particle ◽  
General Corrosion ◽  
Pure Aluminium ◽  
Structure And Properties ◽  
Columnar Crystal ◽  
Sample Depth ◽  
Powder Particles

The paper investigates the structure and properties of samples made of ASP-25 AlSi10Mg, a Russian powder designed to replace expensive additive manufacturing powders of European origin featuring the same chemical composition. We detected that the particle size in the ASP-25 AlSi10Mg powder varies in the range of 7 to 50 μm, the average particle size being 23 μm for the standard deviation of 9.15 and dispersion of 83.7. On the surface of powder particles, we observed smaller satellite particles, individual aggregates, and particles of pure aluminium. We detected the following at the transition boundary between adjacent tracks: a columnar crystal zone and a heat-affected zone consisting of three layers of large, medium and small grains generated as a result of varied cooling conditions. These grains display different silicon lattice thicknesses along their boundaries. We detected no critical size pores (over 15 μm) or burning in the heat-affected zone. The fact that microhardness increases towards the sample edges and is non-monotonic over the transverse section is due to a range of factors acting simultaneously to create non-uniform temperature and force fields that cause differences in conditions of structure formation. Fractography studies of fractures in the AlSi10Mg alloy showed that the nature of failure varies along the sample depth. The central part of the sample, which is subjected to the highest thermal effects, shows clear signs of viscous failure along the main cracks developing along the boundaries of construction layers. We showed that the AlSi10Mg alloy is more resistant to pitting corrosion and general corrosion than the AK9сh (AK9ч) alloy

scholarly journals Influence of Glass Powder Size Sorting on Properties of Composite Systems

2016 ◽  
Vol 47 (1) ◽  
pp. 25-31
Author(s):  
K. Dědičová ◽  
P. Valášek
Keyword(s):  
Glass Powder ◽  
Adhesive Bonding ◽  
Raw Materials ◽  
Average Particle Size ◽  
Polymeric Materials ◽  
Average Particle ◽  
Powder Size ◽  
Size Sorting ◽  
Powder Particles ◽  
Size Of Particles

Abstract Glass powder ranks among the secondary raw materials, which can be used in the interaction with polymeric materials. In the present experiment the polymeric/epoxy particle composite with different sizes of glass powder particles is described. Such utilization of recyclable materials is environmental-friendly and should be preferred. The size of particles forming the filler of the described composites is one of the key characteristics affecting the mechanical properties. Due to the properties of the systems filled with glass powder, these materials can potentially be used in agriculture (renovations, adhesive bonding, cementing, etc.). In the experiment, glass powder was dimensionally sorted through sieves. Three fractions of glass powder with particles size of 0−30, 30−50, and 50−90 μm were created and utilized, the average particle size being 18.7, 38.7, and 72.6 μm, respectively. The interaction of the 18.7 μm particles did not lead to a statistically significant decrease of shear strength values in the interval 0−20 vol.%. The presence of glass powder, however, in all cases decreased tensile strength.

scholarly journals STUDY PARTICLE SIZE DISTRIBUTION OF ERODING POWDER LEAD BRONZES OBTAINED IN DISTILLED WATER

2018 ◽  
Vol 22 (4) ◽  
pp. 42-49
Author(s):  
E. V. Ageev ◽  
A. S. Pereverzev ◽  
A. S. Osminina ◽  
I. Yu. Grigorov
Keyword(s):  
Particle Size ◽  
Average Particle Size ◽  
Discharge Zone ◽  
Powder Materials ◽  
Average Particle ◽  
Distilled Water ◽  
Powder Particles ◽  
Local Exposure ◽  
Finely Dispersed Powder ◽  
Powder Lead

The article is devoted to the current problem of processing waste of conductive materials, in particular lead bronze, which accumulates in large quantities at enterprises. A promising method for processing any conductive material, characterized by wastelessness, ecological purity of the process, and low energy costs, is the method of electroerosive dispersion. The essence of the method of electroerosive dispersion is the destruction of current-conducting material as a result of local exposure to short-term electrical discharges between the electrodes. In the discharge zone, under high temperatures, heating, melting and partial evaporation of the material occurs, resulting in the formation of finely dispersed powder particles. At the same time, the electrical parameters of the installation will affect the productivity of the process for obtaining powder materials: the voltage at the electrodes, the capacitance of the discharge capacitors, and the repetition rate. The article presents the results of the analysis of particles of powdered lead bronze obtained by the method of electroerosive dispersion in distilled water from wastes, using the laser analyzer of particle sizes "Analysette 22 NanoTec". It has been experimentally established that the average particle size of powdered lead bronze is 9.73 μm, the arithmetic value is 9.731 μm. It was also found that the elongation coefficient (elongation) of particles with a size of 7.188 μm is 1.50.

scholarly journals Description, Kinetic and Equilibrium Studies of the Adsorption of Carbon Dioxide in Mesoporous Iron Oxide Nanospheres

2021 ◽  
Vol 12 (1) ◽  
pp. 1022-1038
Keyword(s):  
Iron Oxide ◽  
High Efficiency ◽  
Co2 Adsorption ◽  
Average Particle Size ◽  
Bet Surface Area ◽  
Average Particle ◽  
Equilibrium Studies ◽  
Spherical Form ◽  
Best Fit

Mesoporous iron oxide nanospheres (MINs) have been successfully synthesized and have proven to be high-efficiency adsorbents. The morphology of the MINs is very uniform in spherical form, with an average particle size of 23-27 nm in the diameter range. MINs content has a fairly high BET surface area of 188.25 m2g−1 and a total volume of 0.14 cm3g−1 pores. Thus, seams were seen as potential CO2 sequestration reservoirs to reduce greenhouse gas emissions. The CO2 adsorption was favorable at low temperature and dry MINs conditions. However, MINs have a high adsorption capacity of 0.15 mmol/g. The CO2 adsorption isotherm of all coal samples according to the IUPAC classification of adsorption isotherms fits category I, which most likely explains adsorption confined to a few layers of molecules (micropores and mesopores). The balancing assessment using Langmuir, Henry, Dubbin, Temkin, Toth, Harkins-Jura, Elovich, Redlich-Peterson, and Josene model provided the best fit for any experimental adsorption data that predict heterogeneous surface properties of MINs.

scholarly journals The effect of reversing current deposition on the apparent density of electrolytic copper powder

2002 ◽  
Vol 67 (1) ◽  
pp. 61-67 ◽  
Author(s):  
Konstantin Popov ◽  
Ljubica Pavlovic ◽  
Evica Ivanovic ◽  
Velimir Radmilovic ◽  
Miomir Pavlovic
Keyword(s):  
Apparent Density ◽  
Copper Powder ◽  
Particle Morphology ◽  
Electrolytic Copper ◽  
Current Wave ◽  
Electrolytic Copper Powder ◽  
Copper Powders ◽  
Morphology And Structure ◽  
Powder Particles

The possibility of depositing copper powders with different apparent density by changing the shape of reversing current wave is shown. The morphology and crystallinity of powder particles can be varied considerably by changing shape of the reversing current wave and, hence, the apparent density of powders. The relation of apparent density with particle morphology and structure was illustrated.

Effect of the Compaction Parameters and Canning Material of Nanostructured Al-Powder Consolidated via Intense Plastic Straining Process

2008 ◽  
Author(s):  
H. G. Salem ◽  
M. Shamma
Keyword(s):  
Equal Channel Angular Extrusion ◽  
Average Particle Size ◽  
Research Work ◽  
High Strength ◽  
Processing Parameters ◽  
Average Particle ◽  
Particle Rotation ◽  
Sample Density ◽  
Powder Particles ◽  
Al 2024

Research groups around the world have reached common and contradicting conclusions regarding the behavior and properties of nanostructured materials. The aim of this research is to affirm the common findings by previous research, and support one of the currently proposed concepts of mechanical behavior based on processing and characterization of consolidated nanocrystalline micropowders of high strength/precipitation hardenable aluminum alloy using combined PM/intense plastic straining via Equal Channel angular Extrusion (ECAE). This research work investigated the effect of (a) Cold and hot consolidation of nanocrystalline Al-2124 micropowders into compacts with 4.0 h/d ratio and (b) Canning material used for encapsulating the compact rods for subsequent extrusion within the ECAE channels, and (c) the effect of ECAE number of passes and routes on the green compact properties. The effect of the processing parameters (compaction condition, extrusion temperature, strain rate) on the sample density, grain, subgrain and subcell sizes, and hardness was studied. Pure wrought and cast Cu, and casts Al-cans as well as Al-2024 wrought cans were used for canning of the consolidated powders. Green and hot compact rods were produced from 40μm average particle size Al-2124 powders with 53nm internal structure. Highest density consolidated rods were produced for the double sided cold compaction at 6σ (450MPa) over duration of 30min, while single sided compaction at similar pressure over 60min duration time of compaction and at temperature of 480°C produced the most dense and highest hardness hot compacts. Pure wrought Cu and cast Al are the most suitable canning material for room temperature ECAE of the Al-2124 green compacts. Non-isothermal heating during extrusion hindered the uniform warm deformation of the green and hot compacts canned in wrought Al-2024. Loose powder particles of the green compacts results in particle rotation while passing though the 90° angle intersecting channels of ECAE, and hence prevents full consolidation and densification of the produced product.

scholarly journals Preparation of W-C-Co Composite Micropowder with Spherical Shaped Particles Using Plasma Technologies

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4258
Author(s):  
Andrey Samokhin ◽  
Nikolay Alekseev ◽  
Aleksey Astashov ◽  
Aleksey Dorofeev ◽  
Andrey Fadeev ◽  
...  
Keyword(s):  
Particle Size ◽  
Plasma Treatment ◽  
Average Particle Size ◽  
Spherical Particles ◽  
Average Particle ◽  
Dense Microstructure ◽  
Scale Range ◽  
Powder Particles ◽  
Phase And Chemical Composition ◽  
Average Size

The possibility of obtaining composite micropowders of the W-C-Co system with a spherical particle shape having a submicron/nanoscale internal structure was experimentally confirmed. In the course of work carried out, W-C-Co system nanopowders with the average particle size of approximately 50 nm were produced by plasma-chemical synthesis. This method resulted in the uniform distribution of W, Co and C among the nanoparticles of the powder in the nanometer scale range. Dense microgranules with an average size of 40 microns were obtained from the nanopowders by spray drying. The spherical micropowders with an average particle size of 20 microns were received as a result of plasma treatment of 25.36 microns microgranule fraction. The spherical particles obtained in the experiments had a predominantly dense microstructure and had no internal cavities. The influence of plasma treatment process parameters on dispersity, phase, and chemical composition of spherical micropowders and powder particles microstructure has been established.

Investigation of the Properties of Powder Materials Using Computer Modeling

2021 ◽  
Vol 1038 ◽  
pp. 33-39
Author(s):  
Viktoriya Pasternak ◽  
Lyudmila Samchuk ◽  
Nataliia Huliieva ◽  
Igor Andrushchak ◽  
Artem Ruban
Keyword(s):  
Fractional Composition ◽  
Average Particle Size ◽  
Three Dimensional ◽  
Average Diameter ◽  
Powder Materials ◽  
Average Particle ◽  
Inhomogeneous Materials ◽  
Cross Sectional ◽  
Powder Particles ◽  
Granulometric Characteristics

Granulometric characteristics of structurally inhomogeneous materials based on full-scale mounds of a powder mixture of different fractional composition are established. Regularities of backfilling of powder particles of different shapes and sizes are revealed, and changes in the polydispersity of powder particles within each fraction are justified. It is proved that with a decrease in the average particle size of structurally inhomogeneous AlCu2 materials in a single fraction, the size spread relative to this value of other particles increases. The results of calculating the porosity of backfills with particles of various shapes (round, triangular, and square) depending on the cross-sectional area of the lobules are presented. A three-dimensional diagram is constructed that shows the relationships between the fractional composition of powder particles, their average diameter, and the degree of inhomogeneity of homogeneous bronze AlCu2.

scholarly journals Planetary Milling and Self-Propagating High-Temperature Synthesis of Al-TiB2 Composites

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1050 ◽  
Author(s):  
Alexey Matveev ◽  
Ilya Zhukov ◽  
Mansur Ziatdinov ◽  
Alexander Zhukov
Keyword(s):  
Powder Mixture ◽  
Average Particle Size ◽  
Aluminum Matrix ◽  
Average Particle ◽  
Initial Powder ◽  
Time Increase ◽  
Reaction Products ◽  
Temperature Synthesis ◽  
High Temperature Synthesis ◽  
Powder Particles

The paper explores the influence of planetary milling on the temperature and velocity of Al-Ti-B powder mixture combustion and also on the structure and phase composition of the reaction products. It is found that the time increase of planetary milling modifies the structure of the powder particles, improves the density of compacted specimens, and increases the temperature and velocity of their combustion. These time dependences are extreme, with maximum values during 180 s planetary milling. Experiments show that the reaction products consist of an aluminum matrix with uniformly distributed particles of titanium diboride of not over 1 µm in size. The average particle size changes with the increase in the time of the planetary milling of the initial powder mixture.

Sign in / Sign up

Export Citation Format

Share Document