scholarly journals Exploring Mechanical Alloying to Produce Doped ZnO

2019 ◽  
Vol 1 (3) ◽  
pp. 1
Author(s):  
Belén Sotillo ◽  
María Esther Solana ◽  
Paloma Fernández
Keyword(s):  
Mechanical Alloying ◽  
Lattice Parameter ◽  
Grinding Process ◽  
Particle Sizes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Doped Zno

In this work, a mixture of ZnO and CeO2 powders are subjected to a milling procedure to monitor the mechanical alloying processes. ZnO-CeO2 powders have been milled during 10 to 60 hours, and have been characterized by X-ray diffraction (XRD), UV-Vis absorption, Raman and photoluminescence spectroscopies, in order to study the present phases, the tensional state of material and particle sizes. The evolution of the phases presents with the time of milling, and the possible changes in the lattice parameter will help us to estimate the efficiency of the grinding process for obtaining Ce doped ZnO.

Elaboration, Structure and Mössbauer Spectroscopy of Nanostructured Fe100−xSix Powders Elaborated by Mechanical Alloying

SPIN ◽  
2017 ◽  
Vol 07 (02) ◽  
pp. 1750002 ◽  
Author(s):  
M. Hemmous ◽  
A. Guittoum
Keyword(s):  
Magnetic Field ◽  
Solid Solution ◽  
Mechanical Alloying ◽  
Hyperfine Magnetic Field ◽  
Lattice Parameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
Grain Sizes ◽  
The Mean ◽  
Xrd Studies

We have studied the effect of the silicon concentration on the structural and hyperfine properties of nanostructured Fe[Formula: see text]Six powders ([Formula: see text], 20, 25 and 30[Formula: see text]at.%) prepared by mechanical alloying. The X-ray diffraction (XRD) studies indicated that after 72[Formula: see text]h of milling, the solid solution bcc-[Formula: see text]-Fe(Si) is formed. The grain sizes, [Formula: see text]D[Formula: see text] (nm), decreases with increasing Si concentration and reaches a minimum value of 11[Formula: see text]nm. We have found that the lattice parameter decreases with increasing Si concentration. The changes in values are attributed to the substitutional dissolution of Si in Fe matrix. From the adjustment of Mössbauer spectra, we have shown that the mean hyperfine magnetic field, [Formula: see text]H[Formula: see text] (T), decreases with increasing Si concentration. The substitutional dependence of [Formula: see text]H[Formula: see text] (T) can be attributed to the effect of p electrons Si influencing electrons d of Fe.

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.

Thermodynamic Analysis of the Extension of Solid Solubility of the Cu-Cr System Processed by Mechanical Alloying

2011 ◽  
Vol 311-313 ◽  
pp. 392-395 ◽  
Author(s):  
Kun Yu Shi ◽  
Tao Shen ◽  
Li Hong Xue ◽  
Chun Hao Chen ◽  
You Wei Yan
Keyword(s):  
Mechanical Alloying ◽  
Thermodynamic Analysis ◽  
Solid Solubility ◽  
Structural Changes ◽  
Milling Time ◽  
Solubility Limit ◽  
Lattice Parameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cr System

The nanocrystalline Cu-5wt.%Cr alloy powders were prepared by mechanical alloying. The structural changes were characterized by X-ray diffraction (XRD) technique. A thermodynamic analysis was carried out to predict the change in the solubility limit of this system. It was found that the energy resulting from the MA process is sufficient to increase the solid solubility of immiscible Cr-Cu system. The solid solubility may be extended up to 5 wt.% Cr in Cu after 20 h milling. The formation of the supersaturated solid solution leads to the decrease of Cu lattice parameter. However, it decomposes with the further increase of the milling time, which leads to the increase of Cu lattice parameter.

X-Ray Diffraction Study of a Thin GaAs Film on Si(100)

1987 ◽  
Vol 102 ◽  
Author(s):  
Arun S. Bommannavar ◽  
C. J. Sparks ◽  
A. Habenschuss ◽  
G. E. Ice ◽  
A. Dhere ◽  
...  
Keyword(s):  
Strain Distribution ◽  
Molecular Beam ◽  
Silicon Crystal ◽  
Domain Size ◽  
Lattice Parameter ◽  
Particle Sizes ◽  
Gaas Film ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mosaic Spread

ABSTRACTA 900A single crystalline GaAs film deposited by molecular beam epitaxy (MBE) on a silicon crystal cut 4.1° from (001) surface was characterized with X-ray diffraction measurements of the mosaic spread, particle size and strain distribution, and lattice parameter. The GaAs film had a larger mosaic spread in the direction of the steps of the silicon surface and coherent particle sizes of about 900 Å compared to the estimated film thickness of approximately 1000 Å. Superlattice reflections gave an ordered domain size of about 330 Å. There is a residual strain gradient in the film which is nearly linear with the lattice constant differing by about 0.044 Å between the surface of the film and its interface with the silicon substrate. Lattice parameter measurements indicate a small expansion of 0.13% perpendicular to the plane of the film.

The Influence of Milling Time and Impact Force on the Mutual Diffusion of Al and Cu during Synthesis of Al-4.5wt%Cu Alloy via Mechanical Alloying

2009 ◽  
Vol 283-286 ◽  
pp. 494-498 ◽  
Author(s):  
Ali Mostaed ◽  
Ehsan Mostaed ◽  
Ali Shokuhfar ◽  
H. Saghafian ◽  
Hamid Reza Rezaie
Keyword(s):  
Mechanical Alloying ◽  
Milling Time ◽  
Diffusion Rate ◽  
Impact Force ◽  
Weight Ratio ◽  
Lattice Parameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cu Alloy ◽  
Elemental Diffusion

The study of mechanical alloying (MA) process on the immiscible Al–Cu systems having positive heats of mixing has been investigated by the earlier researchers. However, a comprehensive understanding of the diffusion phenomenon during the mechanical alloying process is still far from complete. The effects of milling time and impact force, defined as the ball-to-powder weight ratio (BPR), on the elemental diffusion during mechanical alloying process of Al-4.5wt%Cu were evaluated in the current work. X-ray diffraction results showed that increasing the milling time and impact force led to increasing the dislocation as because of increasing the micro-strain, lattice parameter and decreasing the crystallite size. As a result of this, the diffusion rate was enhanced. The interpretation of data resulted have been discussed in details.

Crystallisation of Amorphous Al60Fe20Ti15Ni5 Alloy Produced by Mechanical Alloying

2010 ◽  
Vol 163 ◽  
pp. 243-246 ◽  
Author(s):  
Marek Krasnowski ◽  
Tadeusz Kulik
Keyword(s):  
Mechanical Alloying ◽  
Amorphous Phase ◽  
High Energy ◽  
Lattice Parameter ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Elemental Powder Mixture

In the present work, an elemental powder mixture of Al60Fe20Ti15Ni5 (at.%) was mechanically alloyed in a high-energy ball mill. The phase transformations occurring in the material during milling were studied with the use of X-ray diffraction. The results obtained show that an amorphous phase was formed during performed mechanical alloying process. Thermal behaviour of the milling product was examined by differential scanning calorimetry. It was found that amorphous phase crystallised above 540 °C when a heating rate of 40 °C/min was applied. On the basis of X-ray diffraction results, crystallisation product was identified as a cubic phase with the lattice parameter a0 = 11.856 Å, isomorphic with the 2 (Al2FeTi, fcc structure D8a) phase. The mean crystallite size of the crystallised 2 phase was 19 nm.

Microstructure Evolution During Mechanical Alloying of Face Centered Cubic Ti3Si Nanoparticles

2009 ◽  
Vol 6 ◽  
pp. 177-184
Author(s):  
Qiong Wu ◽  
Chang Sheng Li ◽  
Hua Tang ◽  
Xiao Hui Yu ◽  
Ke Sheng Cao ◽  
...  
Keyword(s):  
Mechanical Alloying ◽  
Lattice Parameter ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
X Ray ◽  
Parameter Ratio ◽  
Transmission Electron ◽  
Si Nanoparticles ◽  
Amorphous Compounds ◽  
Face Centered

Face centered cubic Ti3Si nanoparticles were synthesized by mechanical alloying process and the structural and compositional evolutions during the mechanical alloying process were investigated by X-ray diffraction and High Resolution Transmission Electron Microscopy. The results showed that the lattice parameter ratio c/a and the unit cell volume of Ti(Si) were found to decrease with increasing milling time, indicating that the shrinkage of Ti lattice was caused by diffusion of Si atoms into Ti. After milling 51h, amorphous compounds were obtained by alloying Ti and Si powders, and the following mechanical alloying process crystallized the amorphous alloy to crystalline Ti3Si nanoparticles. These nanoparticles were predominantly crystalline with traces of the remnant amorphous phase.

X-Ray Diffraction, Microstructure and Mössbauer Studies of Nanostructured Fe90Mg10 Powders Elaborated by Mechanical Alloying

2016 ◽  
Vol 38 ◽  
pp. 114-123
Author(s):  
A. El Mohri ◽  
A. Guittoum ◽  
K. Taibi ◽  
M. Azzaz
Keyword(s):  
Grain Size ◽  
Mechanical Alloying ◽  
Milling Time ◽  
Particle Morphology ◽  
Lattice Parameter ◽  
Atomic Ratio ◽  
Interfacial Region ◽  
Alloy Formation ◽  
X Ray Diffraction ◽  
X Ray

The mechanical alloying (MA) of elemental powder mixtures of Fe90Mg10 (atomic ratio of 79.67:20.33) was performed in an argon atmosphere using a planetary ball mill process. The alloy formation and the different physical properties were investigated as a function of milling time, t (in the 0–54h range) by means of the X-ray diffraction (XRD) technique, scanning electron microscopy (SEM), and Mössbauer spectroscopy (MS). The formation of the solid solution α-Fe (Mg) started after 4 h of milling. The Mg peaks are completely missing. XRD results also indicated that when the milling time increases, the lattice parameter increases, whereas the grain size decreases and the mean level of microstrains increase. The powder particle morphology was observed by SEM at different stages of milling. The Mössbauer spectra were fitted with two sextets corresponding to the crystalline body centered cubic (bcc) Fe phase and a second sextet which represents supersaturated solid solutions of Mg in (α-Fe). The appearance and the increase in intensity of the second sextet 17, 66 % at (12 h) to 50 % (54 h) with t corresponding to the dissolved Mg in the (α-Fe). This may indicate that the interfacial region effect increases with milling time due to the grain size reduction and to the disordered state of the interfacial region.

Mechanical properties of FeAlSi powders prepared by mechanical alloying from different initial feedstock materials

2019 ◽  
Vol 107 (2) ◽  
pp. 207 ◽  
Author(s):  
Jaroslav Čech ◽  
Petr Haušild ◽  
Miroslav Karlík ◽  
Veronika Kadlecová ◽  
Jiří Čapek ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Alloying ◽  
Young’S Modulus ◽  
Milling Time ◽  
Young's Modulus ◽  
Element Model ◽  
X Ray Diffraction ◽  
X Ray ◽  
Powder Particles ◽  
Complete Homogenization

FeAl20Si20 (wt.%) powders prepared by mechanical alloying from different initial feedstock materials (Fe, Al, Si, FeAl27) were investigated in this study. Scanning electron microscopy, X-ray diffraction and nanoindentation techniques were used to analyze microstructure, phase composition and mechanical properties (hardness and Young’s modulus). Finite element model was developed to account for the decrease in measured values of mechanical properties of powder particles with increasing penetration depth caused by surrounding soft resin used for embedding powder particles. Progressive homogenization of the powders’ microstructure and an increase of hardness and Young’s modulus with milling time were observed and the time for complete homogenization was estimated.

Mechanical Alloying Behavior in the Nb-Si, Ta-Si, and Nb-Ta-Si Systems

1988 ◽  
Vol 133 ◽  
Author(s):  
K. S. Kumar ◽  
S. K. Mannan
Keyword(s):  
High Temperature ◽  
Mechanical Alloying ◽  
Mechanical Milling ◽  
Room Temperature ◽  
Crystalline Compound ◽  
X Ray Diffraction ◽  
X Ray ◽  
Β Phase ◽  
Α Phase

ABSTRACTThe mechanical alloying behavior of elemental powders in the Nb-Si, Ta-Si, and Nb-Ta-Si systems was examined via X-ray diffraction. The line compounds NbSi2 and TaSi2 form as crystalline compounds rather than amorphous products, but Nb5Si3 and Ta5Si3, although chemically analogous, respond very differently to mechanical milling. The Ta5Si3 composition goes directly from elemental powders to an amorphous product, whereas Nb5Si3 forms as a crystalline compound. The Nb5Si3 compound consists of both the tetragonal room-temperature α phase (c/a = 1.8) and the tetragonal high-temperature β phase (c/a = 0.5). Substituting increasing amounts of Ta for Nb in Nb5Si3 initially stabilizes the α-Nb5Si3 structure preferentially, and subsequently inhibits the formation of a crystalline compound.

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