Effect of Mechanical Activation on the Morphology and Microstructure of Ni-Al-Ti-B Composite Powders

2007 ◽  
Vol 353-358 ◽  
pp. 1259-1262
Author(s):  
Guo Jian Cao ◽  
Lin Geng ◽  
Yong Liang Guo ◽  
Masaaki Naka
Keyword(s):  
Particle Size ◽  
Mechanical Activation ◽  
Weight Ratio ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Composite Powders ◽  
Atom Ratio ◽  
X Ray ◽  
Calculation Results ◽  
Effective Grain Size

In this work, Ni-Al-Ti-B composite powders with Ni: Al: Ti: B atom ratio of 5.7: 1.9:1:1 were prepared by using mechanical activation (MA) method. The MA processes were performed by vibration ball mill in a water-cooled chamber for 30 h. The ball-to-powder weight ratio was 10:1. In order to reduce the oxidation of the powders during milling process, ball milling was performed under an Argon atmosphere. The evolution of morphology and microstructure of Ni-Al-Ti-B composite powders were examined at different milling stages using scanning electron microscope and X-ray diffraction. Distribution of powders size was analyzed and the results showed that there were three stages for the change of powders size: (1) at the first stage, powders size increased due to more welding than fracture of the powders within 2h of MA, (2) at the second stage, particle size continuously decreased until 16h of MA due to more fracturing than welding, and (3) after 16h of MA, the particle size remained constant when welding and fracture reached an equilibrium. Calculation results according to Scherrer equation from X-ray pattern showed that the effective grain size continuously decreased with MA time. X-ray diffraction pattern confirmed that the formation of Ni and Ti solid solution during MA process of the Ni-Al-Ti-B composite powders.

Rietveld analysis of mechanically activated BaCO3–TiO2 system

2008 ◽  
Vol 23 (S1) ◽  
pp. S13-S17 ◽  
Author(s):  
Márcio de Sousa Góes ◽  
José Arana Varela ◽  
Carlos de Oliveira Paiva-Santos ◽  
Biljana D. Stojanovic ◽  
André Vitor Chaves de Andrade
Keyword(s):  
Mechanical Activation ◽  
Diffraction Data ◽  
Rietveld Analysis ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Calcination Time ◽  
Calcination Process ◽  
X Ray ◽  
Weight Percentage ◽  
Crystallite Shape

BaTiO3 powders were prepared through mechanical activation chemistry and analyzed by Rietveld refinement with X-ray diffraction data. Raw BaCO3 and TiO2 powders were dry milled for 5 and 20 h and then calcinated for 2 and 4 h at 800 °C. The milling process was found to have broken up the BaCO3 and TiO2 crystals into smaller crystals and formed only small amounts (<1.5 wt%) of BaTiO3. Subsequence calcinations for 2 and 4 h at 800 °C successfully produced large amounts (>97.7 wt%) of BaTiO3 crystals. The calcination process also generated microstrains and crystallite-size anisotropy in BaTiO3. An increase in the calcination time from 2 to 4 h increased the BaTiO3 weight percentage and the crystallite-shape anisotropy, but decreased the tetragonal distortion anisotropic microstrains in BaTiO3 crystals.

An Investigation on the Application of Cryogenic Ball Milling to Ibuprofen Particle and Its Characteristics

2006 ◽  
Vol 505-507 ◽  
pp. 355-360 ◽  
Author(s):  
Kyong Yop Rhee ◽  
Hyun Kab Cho ◽  
Jai Sung Hong
Keyword(s):  
Particle Size ◽  
Ball Milling ◽  
Weight Ratio ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Chemical Changes ◽  
Ball Milling Process ◽  
Particle Size Analyzer ◽  
Before And After ◽  
Size Of Particles

For a present study, a cryogenic ball milling process was applied to reduce the Ibuprofen particles to submicron in order to enlarge their dissolution rate. The cryogenic ball milling was performed using 6 mm zirconia balls at a temperature of -180 °C or lower. The effects of milling time, the weight ratio of ball to Ibuprofen, and milling speed on the particle size were investigated. SEM and particle size analyzer were used to analyze the shape and size of particles before and after ball milling. The chemical changes before and after the cryogenic ball milling process were examined through XRD (x-ray diffraction) analysis. The results show that the size of Ibuprofen particles was reduced to about 1/20 of its initial size and the particle size showed negligible change after six hours of ball milling. The effect of weight ratio and the milling speed on the particle size was almost negligible. The results also show that cryogenic ball milling yielded no chemical changes in the particle.

Characterization of Ni75Mo25 Alloy Prepared by Mechanical Alloying and Heat Treatment

2013 ◽  
Vol 203-204 ◽  
pp. 394-397
Author(s):  
Joanna Panek ◽  
Bożena Bierska-Piech ◽  
Jolanta Niedbała
Keyword(s):  
Heat Treatment ◽  
Mechanical Alloying ◽  
Weight Ratio ◽  
Milling Process ◽  
Particle Sizes ◽  
X Ray Diffraction ◽  
Powder Synthesis ◽  
X Ray ◽  
Microscopy Techniques

The process of Ni75Mo25powder synthesis via mechanical alloying (MA) was studied. Process was carried out from pure elements: Ni and Mo with a particle size under 150 μm. A ball-to-powder weight ratio and the rotational speed were 5:1 and 500 rpm, respectively. Oxidation was reduced by milling under an argon atmosphere. The milling process was performed during up to 60 hours. X-ray diffraction (XRD) and scanning electron microscopy techniques have been used to investigate resulting products. It was found that the particle sizes decrease with the increase in milling time. The resulting powder consists of metastable Ni(Mo) and Mo(Ni) solid solutions. Milled Ni75Mo25 powder was subjected to heat treatment at temperature of 773K, 973K and 1173K. As a result of annealing the formation of Ni4Mo and NiMo intermetallic phases was observed.

Particle Size Distribution and Structural State Analysis of Mechanically Milled Strontium Hexaferrite

2019 ◽  
Vol 946 ◽  
pp. 293-297 ◽  
Author(s):  
Ivan N. Egorov ◽  
Svetlana I. Egorova ◽  
Viktor P. Kryzhanovsky
Keyword(s):  
Particle Size ◽  
Magnetic Fields ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Fluidized Bed ◽  
Milling Process ◽  
Strontium Hexaferrite ◽  
X Ray Diffraction ◽  
X Ray ◽  
Powder Particles

Article presents an experimental study result of milling coarse strontium hexaferrite in beater mill with formation of magneto fluidized bed and without it. Magneto fluidized bed is formed by mutually perpendicular constant and alternating gradient magnetic fields. We studied the dynamics of particle size distribution from milling time and parameters of magnetic fields. Microstructure dynamics of strontium hexaferrite powder particles milled in various regimes was studied by X-ray diffraction methods. Milling efficiency and energy efficiency of milling process were studied in conditions with and without powder fluidization by magnetic fields. Analysis of experimental data showed advantages of milling in magneto fluidized bed in increased efficiency, particle size distribution homogeneity and powder chemical activity because of lattice micro-stresses.

Research on Mechanochemical of Silica and its Composite Powders

2014 ◽  
Vol 881-883 ◽  
pp. 1487-1491 ◽  
Author(s):  
Jing Jing Zhu ◽  
Hua Zhi Gu ◽  
Tian Xing Peng ◽  
Bao Hua Sun
Keyword(s):  
Particle Size ◽  
Crystal Size ◽  
Lattice Distortion ◽  
X Ray Diffraction ◽  
Composite Powders ◽  
X Ray ◽  
Peak Intensity ◽  
Area Increase ◽  
Surface Area Increase ◽  
Grinding Time

Silca and its composite powders added different amount of microsilica were ground in a planetary ball mill (QM-3SP4) at various grinding period with addition of a certain number of grinding aid. The effects of mechano-chemical on particle size, crystal size and lattice deformation in grinding process were analyzed. The phase compositions and size compositions of the treated powders were investigated by X-ray Diffraction (XRD) and Laser Particle Size Analyzers. With the increase of grinding time, the particle size decrease, the specific surface area increase, and the more amount of microsilica added, the smaller particle size the powders had after grinding. The XRD results showed that the diffraction peak intensity of powders weaken and gradually widen. The surface of the particle happened to amorphization, and occurred grain refinement and lattice distortion. Comparing with other treated powders, the change of the powders with the microsilica addition of 5% was larger. Even though the grinding time reached to 30h, the crystal transformation of SiO2has not been detected.

scholarly journals Analysis of the influence of β-TCP particle size on deagglomeration processes

2020 ◽  
Vol 9 (4) ◽  
pp. e175943067
Author(s):  
João Augusto Martins Almeida ◽  
Bruna Horta Bastos Kuffner ◽  
Gilbert Silva ◽  
Patrícia Capellato ◽  
Daniela Sachs
Keyword(s):  
Particle Size ◽  
Ball Milling ◽  
High Energy ◽  
Milling Process ◽  
High Energy Ball Milling ◽  
X Ray Diffraction ◽  
Powder Morphology ◽  
Heterogeneous Distribution ◽  
X Ray ◽  
Energy Ball

There are a class of material widely used in bone tissue repair. This material is calcium phosphate ceramics (CPCs)that can be used on two phases: α and β. However, β-TCP is more used in bone regeneration than α–TCP due to the biocompatible and bioactive properties.In the present work evaluate the influence of these two distinct processes to deagglomeration and the consequence in the particle size of the β-TCP obtained through solid-state reaction. Among all of the routes used in research and industry to reduce the particles size of different materials, the high energy ball milling is one of the most effective, due to the high rotation speed that this process achieves. The deagglomeration through agate mortar is considered a cheaper process when compared with the high energy ball milling. The characterization of both powders, deagglomerated in high energy ball milling and agate mortar, was realized through scanning electron microscopy, to analyze the powder morphology, and laser granulometry, to determine the size of the particles. Also, the forerunner powder was previously submitted to x-ray diffraction to confirm the formation of the β-TCP phase. The analysis through x-ray diffraction confirmed that the phase formed during the calcination process corresponded to the β-TCP. The results obtained after the deagglomeration processes indicated that the morphology was predominantly irregular for both powders. In relation to the granulometry, the deagglomeration performed through agate mortar showed to produce particles with smaller size (11,4µm e 0,9µm) and heterogeneous distribution, while the high energy ball milling process produced particles with larger size (11,4µm a 1,8µm) and higher homogeneity.

Mechanical Alloying of Fe-Nb-N with Different Ball to Powder Weight Ratio for the Formation of Fe-NbC Composite

2012 ◽  
Vol 620 ◽  
pp. 94-98 ◽  
Author(s):  
Siti Zalifah Md Rasib ◽  
Zuhailawati Hussain
Keyword(s):  
Mechanical Alloying ◽  
Weight Ratio ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Microstructure Characteristics ◽  
Scanning Electron Microscopic ◽  
Small Crystallite

Milling process through mechanical alloying method was performed on a powder mixture of Fe-80.11 wt%, Nb-17.62 wt% and C-2.26 wt% to produce Fe-NbC composite by in situ reaction. Ball to powder weight ratio parameter was selected since formation of phase and microstructure characteristics of this composite were expected to depend on ball collision event during milling. The as-milled and sintered Fe-NbC was characterized by X-ray diffraction (XRD) and Scanning Electron Microscopic (SEM). We found that formation of Fe-NbC by in situ required mechanical alloying of the mixture using 10:1 of ball to powder weight ratio to achieve small crystallite size and more homogeneous of NbC phase.

scholarly journals Mechanical properties of the Al-Mg/MWCNTs composite powders: The effects of ball milling process parameters

2021 ◽  
Author(s):  
Hossein Ahmadian
Keyword(s):  
Mechanical Properties ◽  
Ball Milling ◽  
Milling Time ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Composite Powders ◽  
X Ray ◽  
Ball Milling Process ◽  
Carbon Nano Tubes ◽  
Ball Milling Time

Abstract The effects of multi-walled carbon nano-tubes (MWCNTs) and the ball milling parameters on the mechanical properties of the Al-Mg alloy powders were investigated. Three different composite powders were synthesized through ball-milling process at different time and milling rates. The microstructural and phase analyses were carried out via scanning electron microscopy and X-ray diffraction spectroscopy, respectively. The results indicated that increasing the ball-milling time and rate would lead to the formation of finer particles, which consequently intensifies the plastic deformation and then, results in lower crystallite size. The morphological investigations indicated that while the MWCNTs agglomerates in lower milling rates, increased milling rate not only improve the distribution of the MWCNTs, but also decreases the length of the nano-tubes and promotes their diffusion into Al-Mg matrix. The formation of Al-Mg intermetallic phases through the ball-milling process of the composite powders was also confirmed via microstructural investigations.

Effect of Milling Parameters on Morphology and Grain Size of WO3 and Al Particles for Fabricating WO3/Al Composites

2010 ◽  
Vol 638-642 ◽  
pp. 939-943
Author(s):  
Q.W. Wang ◽  
Y.C. Feng ◽  
Guo Hua Fan ◽  
Gui Song Wang ◽  
Lin Geng
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Milling Time ◽  
Marked Change ◽  
Weight Ratio ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Aluminum Particles ◽  
Milling Parameters ◽  
Electronic Microscope

In this paper, the milling process of WO3 and aluminum particles is studied. Influences of rotate rate, milling time and ball-to-powder weight ratio on the morphology and grain size of the particles are studied by scanning electronic microscope and X-ray diffraction techniques. Al particle size decreases firstly and then increases with increasing milling time, while Al grain size decreases gradually as the milling time increases. WO3 particle is distributed uniformly in Al particles after milling for 9h, and has no marked change as further extension of milling time. With increasing the ball-to-powder weight ratio and rotate rate, both particle size and grain size of Al decreases. milling parameters have almost no effect on the grain size of the WO3 particles.

scholarly journals Mining Wastes of an Albite Deposit as Raw Materials for Vitrified Mullite Ceramics

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 232
Author(s):  
Pedro J. Sánchez-Soto ◽  
Eduardo Garzón ◽  
Luis Pérez-Villarejo ◽  
George N. Angelopoulos ◽  
Dolores Eliche-Quesada
Keyword(s):  
Particle Size ◽  
Raw Materials ◽  
Phase Evolution ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Mining Wastes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Maximum Value

In this work, an examination of mining wastes of an albite deposit in south Spain was carried out using X-ray Fluorescence (XRF), X-ray diffraction (XRD), particle size analysis, thermo-dilatometry and Differential Thermal Analysis (DTA) and Thermogravimetric (TG) analysis, followed by the determination of the main ceramic properties. The albite content in two selected samples was high (65–40 wt. %), accompanied by quartz (25–40 wt. %) and other minor minerals identified by XRD, mainly kaolinite, in agreement with the high content of silica and alumina determined by XRF. The content of Na2O was in the range 5.44–3.09 wt. %, being associated with albite. The iron content was very low (<0.75 wt. %). The kaolinite content in the waste was estimated from ~8 to 32 wt. %. The particle size analysis indicated values of 11–31 wt. % of particles <63 µm. The ceramic properties of fired samples (1000–1350 °C) showed progressive shrinkage by the thermal effect, with water absorption and open porosity almost at zero at 1200–1250 °C. At 1200 °C, the bulk density reached a maximum value of 2.38 g/cm3. An abrupt change in the phase evolution by XRD was found from 1150 to 1200 °C, with the disappearance of albite by melting in accordance with the predictions of the phase diagram SiO2-Al2O3-Na2O and the system albite-quartz. These fired materials contained as main crystalline phases quartz and mullite. Quartz was present in the raw samples and mullite was formed by decomposition of kaolinite. The observation of mullite forming needle-shape crystals was revealed by Scanning Electron Microscopy (SEM). The formation of fully densified and vitrified mullite materials by firing treatments was demonstrated.

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