Sinthesis and Characterization of Nd2Fe14B Powder from Nd-Fe-B Flakes by Wet Mechanical Milling and Heat Treatment

2016 ◽  
Vol 864 ◽  
pp. 70-74 ◽  
Author(s):  
Priyo Sardjono ◽  
Muljadi ◽  
Suprapedi ◽  
Nenen Rusnaeni Djauhari
Keyword(s):  
Particle Size ◽  
Mechanical Milling ◽  
Permanent Magnets ◽  
Magnetic Phase ◽  
Fine Powder ◽  
Xrd Analysis ◽  
High Energy ◽  
Milling Process ◽  
Raw Material ◽  
Milling Method

The Nyodimium-Iron-Boron (Nd-Fe-B) based materials are known as the best type of magnetic materials and it contains a magnetic phase Nd2Fe14B. The Nd-Fe-B alloy Flakes is one of the main raw material for producing of NdFeB-based permanent magnets and the size of Nd-Fe-B flakes are still coarse. Synthesis of Nd2Fe14B powder has been done by a wet mechanical milling method using the High Energy Milling (HEM) for 10 hrs and continued by heating at 600°C in vacuum condition (10-4 Pa). This process is used to produce a fine powder Nd2Fe14B for making of permanent magnets. The milling medium was used a toluene (pa-Emerck)) to protect of particle from oxidation during the milling process. After milling processes, the samples were measured distribution particle size by using Particle Size Analyzer (PSA). Microstructure analysis has been conducted by using X-ray diffractometer (XRD) and Scanning Electron Microscope (SEM/EDX) for samples before milling and sample after heating. The characterization results show that after milling 10 hours, it was obtained fine powder with average size about 1.35 μm. According to SEM/EDX and XRD analysis show that the crystal structure of the sample before milling was different compared to the sample after heating. It is found new magnetic phase with formula Nd2Fe14B.

Synthesis and Characterization of Electromagnetic Material Based On Composite of Barium M-Ferrite and Zinc Oxide

2018 ◽  
pp. 78-82
Author(s):  
Verryon Harahap ◽  
Syahrul Humaidi ◽  
Perdamean Sebayang
Keyword(s):  
Zinc Oxide ◽  
Magnetic Properties ◽  
High Energy ◽  
Lattice Parameter ◽  
Milling Process ◽  
Raw Material ◽  
Wet Milling ◽  
Hexagonal Crystal ◽  
Milling Method ◽  
Energy Products

The making of composites BaFe12O19/ZnO has been done with Wet Milling method used media toluene. Barium M-Ferrit as a matrix and Zinc Oxide as a filler used as the main raw material for composite manufacturing. The milling process of Barium M-Ferrit was done for 12 hours using the High Energy Milling (HEM). Furthermore, the calcination process used furnace at 900 ° C for 4 hours. While Zinc Oxide is milled for 3 hours and calcined at a temperature of 500 oC for 3 hours. The results of Barium M-Ferrit and zinc Oxide mixed using wet milling touluene media for 15 minutes and dried for 1 hour at 200 oC. X-ray diffraction (XRD) showed that BaFe12O19 as a matrix and ZnO as filler with hexagonal crystal structure was formed and the peak showed a single phase, where each BaFe12O19 lattice parameter a = 5.8930 Å, c = 23.1940 Å and ZnO lattice parameter a = 3.2533 Å, c = 5.2073 Å. Characterization Vibrating Sample Magnetometer (VSM) obtained the value of magnetic properties BaFe12O19 powder (matrix) obtained (Ms) magnetic saturation 54.03 emu/g, (Mr) magnet remanent 33.06 emu/g, (Hcj) coercivity 2943 Oe and (BHmax) product energy 190 kGOe and Zinc Oxide as filler values (Ms) magnet saturation 7.84 emu / g, (Mr) magnet remanent 1.27 emu/g, (Hcj) coercivity 152.4 Oe and (BHmax) energy products 10 kGOe. The results of XRD on 50% mass of composites ZnO additions using match software have two phases, namely the presence of ZnO and BaFe12O19 phases which indicate that heterogeneous structures with hexagonal crystal structures. Composite magnetic properties obtained by adding 50% mass of ZnO were (Mr) magnet 39.40 emu/ g, coercivity 2728 Oe, (BHmax) product energy 110 kGOe and for composites 75% mass addition ZnO remanent 39.36 emu/g with coefficient of 1365 Oe and ( BHmax) product energy was 60 kGOe.

scholarly journals A New Method to Recycle Stainless–Steel Duplex UNS S31803 Chips

Metals ◽  
2018 ◽  
Vol 8 (7) ◽  
pp. 546 ◽  
Author(s):  
Mendonça Claudiney ◽  
Oliveira Adhimar ◽  
Sachs Daniela ◽  
Capellato Patricia ◽  
Ribeiro Vander ◽  
...  
Keyword(s):  
Particle Size ◽  
Stainless Steel ◽  
Duplex Stainless Steel ◽  
Mechanical Milling ◽  
Vanadium Carbide ◽  
Initial Density ◽  
High Energy ◽  
Industrial Sector ◽  
Milling Process ◽  
New Method

Due to the increased consumption of raw materials, energy, and the waste it generates, recycling has become very important and fundamental for the environment and the industrial sector. The production of duplex stainless–steel powders with the addition of vanadium carbide in the high energy mechanical milling process is a new method for recycling materials for the manufacture of components in the industrial sector. This study aims to reuse the chips from the duplex stainless–steel UNS S31803 by powder metallurgy with the addition of Vanadium carbide (VC). The mechanical milling was performed using a planetary ball mill for 50 h at a milling speed of 350 rpm and a ball-to-powder weight ratio of 20:1, and the addition of 3 wt % of VC. The material submitted to milling with an addition of carbide has a particle size of less than 140 μm. After milling, the sample went through a stress relief treatment performed at 1050 °C for 1 h and the isostatic compaction process loaded with 300 MPa. The sintered powders and material was characterized by scanning electron microscopy, X-ray diffraction, and micro-hardness tests. The milling process with an addition of 3% VC produced a particle size smaller than the initial chip size. The measurement of micrometric sizes obtained was between 26 and 132 μm. The sintered material had a measurement of porosity evaluated at 15%. The obtained density of the material was 84% compared to the initial density of the material as stainless–steel duplex UNS S31803. The value of the microhardness measurement was 232 HV. The material submitted for grinding presented the formation of a martensitic structure and after the thermal treatment, the presence of ferrite and austenite phases was observed. Thus, in conclusion, this study demonstrates the efficacy in the production of a metal-ceramic composite using a new method to recycle stainless–steel duplex UNS S31803 chips.

Modeling Mechanical Milling Process for Synthesis of Graphite Nanoparticles and their Characterization

2014 ◽  
Vol 922 ◽  
pp. 586-591 ◽  
Author(s):  
Himanshu Panjiar ◽  
R.P. Gakkhar ◽  
B.S.S. Daniel
Keyword(s):  
Particle Size ◽  
Electron Microscope ◽  
Mechanical Milling ◽  
Milling Time ◽  
High Energy ◽  
Milling Process ◽  
X Ray ◽  
Transmission Electron ◽  
Heat Treated ◽  
Graphite Nanoparticles

The synthesis of graphite nanoparticles at ambient temperature by high energy mechanical milling is modelled using ANN (Artificial Neural Network). The effect of milling time on the evolution of particle size, inclusion, microstructure and morphology were examined using XRD (X-Ray Diffraction), EDS (Energy Dispersive X-Ray Spectroscopy), SEM (Scanning Electron Microscope) and TEM (Transmission Electron Microscope). ANN was effectively used to predict the influence of milling time on particle size and to forecast the milling time for the formation of nanoparticles. XRD results of investigation revealed change in strain behaviour of graphite particles of different sizes when heat treated.

Fe3O4 Magnetic Preparation by Bauxite Ore Washing Fine Mud

2014 ◽  
Vol 1010-1012 ◽  
pp. 961-965
Author(s):  
Jian Qiang Xiao ◽  
Guo Wei He ◽  
Yan Jin Hu
Keyword(s):  
Particle Size ◽  
Aging Time ◽  
Average Particle Size ◽  
Xrd Analysis ◽  
Test Methods ◽  
Raw Material ◽  
Molar Ratio ◽  
Average Particle ◽  
Experimental Conditions ◽  
Particle Size Analyzer

Bauxite waste sludge as a raw material, the use of reverse chemical coprecipitation synthesize Fe3O4. Researching temperature, precipitation concentration, aging time and Fe2+/Fe3+ molar ratio effect on the particle size, morphology. Optimal experimental conditions: temperature 70 °C, the precipitant NaOH mass ratio of 10%, aging time 3h, Fe2+/Fe3+ molar ratio of 2:3. Test methods using a laser particle size analyzer, XRD analysis of the products were characterized, the product is Fe3O4, the average particle size of 0.11mm.

scholarly journals Magnetic Properties of SmCo5 + 10 wt% Fe Exchange-Coupled Nanocomposites Produced from Recycled SmCo5

Nanomaterials ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1308 ◽  
Author(s):  
Arnab Chakraborty ◽  
Răzvan Hirian ◽  
Gregor Kapun ◽  
Viorel Pop
Keyword(s):  
Heat Treatment ◽  
Exchange Coupling ◽  
Permanent Magnets ◽  
High Energy ◽  
Raw Material ◽  
Energy Ball ◽  
Hydrogen Decrepitation ◽  
Energy Products ◽  
First Time ◽  
Recycled Material

Nanostructured alloy powders of SmCo5 + 10 wt% Fe obtained using recycled material were studied for the first time. The SmCo5 precursor was obtained from commercial magnets recycled by hydrogen decrepitation. The results were compared with identically processed samples obtained using virgin SmCo5 raw material. The samples were synthesized by dry high-energy ball-milling and subsequent heat treatment. Robust soft/hard exchange coupling was observed—with large coercivity, which is essential for commercial permanent magnets. The obtained energy products for the recycled material fall between 80% and 95% of those obtained when using virgin SmCo5, depending on milling and annealing times. These results further offer viability of recycling and sustainability in production. These powders and processes are therefore candidates for the next generation of specialized and nanostructured exchange-coupled bulk industrial magnets.

Characterization of Ni-CNTs Nanocomposites Produced by Mechanical Alloying

2013 ◽  
Vol 829 ◽  
pp. 515-519 ◽  
Author(s):  
Shaghayegh Gharegozloo ◽  
Hossein Abdizadeh ◽  
Abolghasem Ataie
Keyword(s):  
Mechanical Milling ◽  
Milling Time ◽  
High Energy ◽  
X Ray Diffraction ◽  
Metal Matrix Nanocomposites ◽  
X Ray ◽  
Milling Method ◽  
Particle Refinement ◽  
Matrix Nanocomposites

The interest in using CNTs as the reinforcement of metal matrix nanocomposites has been growing considerably due to their enhanced properties. In the present work, nickel was reinforced by carbon nanotubes (CNTs) via high energy mechanical milling method. The effects of various amounts of CNTs (5%, 10%, 20% and 30%) and different milling times (1, 5, 10 and 15 hours) were investigated. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and vibrating sample magnetometer (VSM) analysis were used for evaluation of phase composition, morphology and magnetic properties of the samples, respectively. The results showed a homogeneous dispersion of CNTs into the nickel matrix phase by mechanical milling. It was observed that the increase in the milling time, for a particular amount of CNTs, caused a decrease of mean crystallite size from 56 nm to 35 nm. The increase of CNTs amount also resulted in the powder particle refinement. VSM analysis showed that with the increase of CNTs from 0% to 30%, the magnetization of the samples decreases from 52.36 to 30.74 emu/g, and the coercivity of the nanocomposites increases from 61.45 to 114 Oe.

Effects of Milling Techniques and Calcinations Temperature on the Composite Cathode Powder LSCF-SDC Carbonate

2014 ◽  
Vol 893 ◽  
pp. 325-328
Author(s):  
M.S.A. Bakar ◽  
Sufizar Ahmad ◽  
H.A. Rahman ◽  
M.A.F.M. Tasrim ◽  
H. Basri ◽  
...  
Keyword(s):  
Fine Fraction ◽  
Xrd Analysis ◽  
Composite Cathode ◽  
High Energy ◽  
Wet Milling ◽  
Composite Cathodes ◽  
Clear Peak ◽  
Milling Method ◽  
Crystallite Structure ◽  
Ball Milling Technique

Composite cathode La0.6Sr0.4Co0.2Fe0.8O3-δ-SDC carbonates (LSCF-SDCC) for applications of low temperature solid oxide fuel cell (LTSOFC) were developed. LSCF-SDCC were mixed using high energy ball milling technique via dry and wet milling method followed by calcinations at 700, 750 and 800 °C. The findings reveal that different calcinations temperature and milling techniques gives effects to the composite cathodes powder. Clear peak intensity demonstrate from wet milling technique as confirm via XRD analysis indicates that crystalline structure has been improved. FESEM investigation demonstrate the presence of large particles in the resultant powder resulting from the increased calcination temperature. LSCF-SDCC composite cathodes powder produced via wet milling technique have good fine fraction and demonstrates good crystallite structure to be served as cathode of LTSOFC compared to dry milling technique.

XRD and EDS Analysis of Composite Cathode Powders LSCF-SDCC-Ag for Low Temperature Solid Oxide Fuel Cells (LTSOFC)

2015 ◽  
Vol 1087 ◽  
pp. 207-211 ◽  
Author(s):  
M.S.A. Bakar ◽  
Sufizar Ahmad ◽  
Hamimah Abdul Rahman ◽  
H. Basri ◽  
A. Muchtar
Keyword(s):  
Ball Milling ◽  
Xrd Analysis ◽  
Composite Cathode ◽  
High Energy ◽  
Wet Milling ◽  
Energy Dispersion Spectroscopy ◽  
Phase Purity ◽  
Eds Analysis ◽  
Before And After ◽  
Milling Method

X-ray diffraction (XRD) and energy dispersion spectroscopy (EDS) analysis has been conducted on composite cathode powder LSCF-SDCC-Ag. Composite cathode powder LSCF-SDCC has been produced using high energy ball milling via wet milling method through calcinations at 750 °C. The calcined LSCF-SDCC powder then was mixed with Ag (3wt%) then pressed become pellets and sintered at 500, 550 and 600 °C. The phase purity of composite cathode powder LSCF-SDCC-Ag was determined via XRD analysis and elements distributions were observed via EDS-mapping. The SrCO3 phase was emerged after the addition of composite cathode powder LSCF-SDCC with Ag powder. The phase purity of composite cathode powder LSCF-SDCC-Ag were maintained before and after sintered. The variable of sintering temperature also not effect the structure as there were no other secondary constituent emerged as confirmed by XRD sensitivity. EDS analysis shows LSCF-SDCC-Ag produced via ball milling has uniform distribution of elements.

scholarly journals RECYCLING AND ITS USE IN CONCRETE WASTE PROCESSING BY HIGH-SPEED MILLING

2019 ◽  
Vol 21 ◽  
pp. 28-32
Author(s):  
Zdeněk Prošek ◽  
Pavel Tesárek ◽  
Jan Trejbal
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Dynamic Modulus ◽  
High Speed ◽  
Milling Process ◽  
Partial Replacement ◽  
Waste Processing ◽  
Structural Concrete ◽  
High Speed Milling ◽  
Milling Method

This article discusses the possibility of recycling of concrete waste using the high-speed milling method. The resulting of milling is micronize old concrete. Used old concrete was created by crushing of old concrete, which served as a structural concrete for the construction of a supporting column. Two level of milling process was used to recycle old concrete. The main use of waste is the possibility of partial replacement of commonly used binder and microfillers in concrete. For this reason, properties as particle size distribution, dynamic modulus of elasticity, flexural strength and compressive strength were observed. The aim is to replace as much cement as possible while maintaining mechanical properties.

Sign in / Sign up

Export Citation Format

Share Document