The Investigation of Structural and Magnetic Properties at High-Temperature of Nanostructured Fe90-Mg10 Alloys Produced by Mechanical Alloying

2018 ◽  
Vol 54 ◽  
pp. 136-145
Author(s):  
A. El Mohri ◽  
M. Zergoug ◽  
K. Taibi ◽  
M. Azzaz
Keyword(s):  
High Temperature ◽  
Mechanical Alloying ◽  
Milling Time ◽  
High Energy ◽  
Lattice Parameter ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
High Energy Ball Mill ◽  
Energy Ball ◽  
The Mean

Nanocrystalline Fe90Mg10 alloy samples were prepared by mechanical alloying process using planetary high energy ball mill. The prepared powders were characterized using differential thermal analysis (DTA), X-ray diffraction technique (XRD) at high temperature, transmission electron microscopy (TEM), and the vibrating sample magnetometer (VSM). Obtained results are discussed according to milling time. XRD at high temperature results also indicated that when the milling time increases, the lattice parameter and the mean level of grain size increase, whereas the microstrains decrease. The result of the observation by the TEM of the Fe-Mg powders prepared in different milling time, coercive fields derived and Saturation magnetization derived from the hysteresis curves in high temperature are discussed as a function of milling time.

SYNTHESIS OF NANO-CRYSTALLINE Cu-Cr ALLOY BY MECHANICAL ALLOYING

2012 ◽  
Vol 05 ◽  
pp. 496-501 ◽  
Author(s):  
S. SHEIBANI ◽  
S. HESHMATI-MANESH ◽  
A. ATAIE
Keyword(s):  
Mechanical Alloying ◽  
Structural Evolution ◽  
High Energy ◽  
Lattice Parameter ◽  
Control Agent ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Nano Crystalline ◽  
High Energy Ball Mill ◽  
Energy Ball

In this paper, the influence of toluene as the process control agent (PCA) and pre-milling on the extension of solid solubility of 7 wt.% Cr in Cu by mechanical alloying in a high energy ball mill was investigated. The structural evolution and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques, respectively. The solid solution formation at different conditions was analyzed by copper lattice parameter change during the milling process. It was found that both the presence of PCA and pre-milling of Cr powder lead to faster dissolution of Cr . The mean crystallite size was also calculated and showed to be about 10 nm after 80 hours of milling.

One-Step Synthesis of CoFe2O4 Nano-Particles by Mechanical Alloying

2013 ◽  
Vol 829 ◽  
pp. 747-751 ◽  
Author(s):  
Sedigheh Rashidi ◽  
Abolghasem Ataie
Keyword(s):  
Mechanical Alloying ◽  
Single Phase ◽  
Milling Time ◽  
High Energy ◽  
Nano Particles ◽  
Milled Sample ◽  
High Energy Ball Mill ◽  
One Step ◽  
Energy Ball ◽  
The Mean

In this study, cobalt ferrite (CoFe2O4) nanoparticles were synthesized by intensive mechanical alloying of CoCO3 and α-Fe2O3 powder using a planetary high energy ball mill in air without any subsequent heat treatment. Effects of milling time on the phase composition, morphology and magnetic properties of the powders were evaluated using XRD, FESEM and VSM techniques, respectively. XRD results indicated that single phase CoFe2O4 nanoparticles with a mean crystallite size of 15 nm were synthesized after 25 hours of mechanical milling. FESEM images confirmed the formation of uniform nanoparticles and showed that the mean particle size of the milling products was decreased from 51 to 25 nm by increasing the milling time from 20 to 30 hours. VSM measurements of the sample milled for 25 hours revealed a saturation magnetization (Ms) of 52.19 emu/g and coercivity (Hc) of 831.95 Oe, which were higher than those of 20 hours milled sample.

Mechanism of solid-gas reaction for formation of metastable niobium-nitride alloy powders by reactive ball milling

1994 ◽  
Vol 9 (11) ◽  
pp. 2891-2898 ◽  
Author(s):  
El-Eskandarany M. Sherif ◽  
K. Sumiyama ◽  
K. Aoki ◽  
T. Masumoto ◽  
K. Suzuki
Keyword(s):  
Gas Flow ◽  
Metastable Phase ◽  
High Energy ◽  
Lattice Parameter ◽  
Niobium Nitride ◽  
X Ray Diffraction ◽  
Nitrogen Gas ◽  
Transmission Electron ◽  
High Energy Ball Mill ◽  
Energy Ball

We report on the formation of a new metastable phase of niobium-nitride (Nb-N) alloy powders. This nonequilibrium phase has been synthesized by milling elemental niobium (Nb) powders under purified nitrogen gas flow using a high energy ball mill at room temperature. The progress of the solid-gas reaction for the Nb-N system has been followed by means of x-ray diffraction, differential thermal analysis, transmission electron microscopy, and chemical analysis. After 720 ks of milling, the initial bcc-Nb is completely transformed to nonequilibrium-fcc-NbN containing about 50 at. % N. The lattice parameter of the end product fcc-NbN was calculated to be 0.433 nm. In addition, the particle and grain sizes of the completely reacted alloy powders are 3 μm and 5 nm, respectively. This transforms to a mixture of hcp-Nb4N3 and hcp-NbN at the high temperatures, as high as 1150 K.

Atmosphere effects of the amorphization reaction in NiZr by ball milling

1993 ◽  
Vol 8 (2) ◽  
pp. 307-313 ◽  
Author(s):  
K. Aoki ◽  
A. Memezawa ◽  
T. Masumoto
Keyword(s):  
High Energy ◽  
Hydrogen Atmosphere ◽  
Nitrogen Atmosphere ◽  
Gas Absorption ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
High Energy Ball Mill ◽  
Energy Ball

An intermetallic compound c–NiZr and a mixture of elemental powders of nickel and zirconium [Ni50Zr50 (at. %)] have been mechanically ground (MG) and mechanically alloyed (MA), respectively, using a high-energy ball mill in various atmospheres. The products were characterized by x-ray diffraction, transmission electron microscopy, differential scanning calorimetry, and chemical analysis as a function of milling time. An amorphous a–NiZr alloy was prepared by both MG and MA in an argon atmosphere. By MG of NiZr, an amorphous nitride a–NiZrN0.15 was synthesized in a nitrogen atmosphere, while a crystalline hydride c–NiZrH3 was formed in a hydrogen atmosphere. On the other hand, ZrN and ZrH2 were formed by MA in a nitrogen and a hydrogen atmosphere, respectively. The amorphization reaction was observed between ZrH2 and Ni by further MA in a hydrogen atmosphere, and a mixture of a–NiZrxHy (x < 1) and ZrH2 was obtained. However, no amorphization was observed by MA between ZrN and Ni in a nitrogen atmosphere. The effects of the milling atmosphere on the phase formations during MG and MA are discussed based on the gas absorption rate.

scholarly journals Influence of Milling Media on the Mechanical Alloyed W-0.5 wt.% Ti Powder Alloy

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Hadi Jahangiri ◽  
Sultan Sönmez ◽  
M. Lütfi Öveçoğlu
Keyword(s):  
Crystallite Size ◽  
Milling Time ◽  
High Energy ◽  
Lattice Parameter ◽  
Mechanically Alloyed ◽  
High Energy Ball Mill ◽  
Powder Density ◽  
Energy Ball ◽  
Ti Powder ◽  
Milled Powders

The effects of milling atmosphere and mechanical alloying (MA) duration on the effective lattice parameter, crystallite size, lattice strain, and amorphization rate of the W-0.5 wt.% Ti powders were investigated. W-0.5 wt.% Ti powders were mechanically alloyed (MA’d) for 10 h and 20 h in a high energy ball mill. Moreover, morphology of the powders for various MA was analyzed using SEM microscopy. Their powder density was also measured by helium pycnometer. The dry milled agglomerated powders have spherical particle, while wet milled powders have layered morphology. Milling media and increasing of milling time significantly reduce the crystallite size. The smallest crystallite size is 4.93 nm which belonged to the dry milled powders measured by Lorentzian method after 20 hours’ MA. However, after 20 hours, MA’d powders show the biggest crystallite size, as big as 57.07 nm, measured with the same method in ethanol.

Nickel Silicides Synthesized by High Energy Ball Milling

2007 ◽  
Vol 353-358 ◽  
pp. 1625-1628 ◽  
Author(s):  
Gen Shun Ji ◽  
Qin Ma ◽  
Tie Ming Guo ◽  
Qi Zhou ◽  
Jian Gang Jia ◽  
...  
Keyword(s):  
Mechanical Alloying ◽  
Ball Milling ◽  
Milling Time ◽  
High Energy ◽  
Planetary Mill ◽  
High Energy Ball Milling ◽  
X Ray Diffraction ◽  
Microstructure Morphology ◽  
Energy Ball ◽  
Xrd Patterns

The high energy ball milling of Ni-50 atom % Si elemental powder mixtures was carried out using a planetary mill. X-ray diffraction (XRD) was used to identify the phase evolutions during the high energy ball milling period. The microstructure morphology of the powders milled different time was determined by field emission scanning electron microscope (FESEM). The beginning time of mechanical alloying was determined by back scattered electrons (BSE) images. The XRD patterns showed that the nickel peaks intensity and the silicon peaks intensity obviously decreased with milling time increased to 1 hour. BSE images revealed that nickel and silicon powders were not blended uniformly for 1 hour of milling. It was found that NiSi formed as the milling time increased to 5 hours, simultaneously, the nickel peaks and the silicon peaks almost disappeared. That means the obvious mechanical alloying started from 5 hours of milling. BSE images agreed with the result analyzed from XRD patterns. With the milling time further increased from 10 to 75 hours, the NiSi peaks decreased gradually, at the same time, the Ni2Si peaks appeared and then increased gradually.

scholarly journals Synthesis of the Fe-6.5% wt. Si Alloy by Mechanical Alloying

2015 ◽  
Vol 13 ◽  
pp. 109-113 ◽  
Author(s):  
Cristina Daniela Stanciu ◽  
Florin Popa ◽  
Ionel Chicinaş ◽  
Olivier Isnard
Keyword(s):  
Mechanical Alloying ◽  
High Energy ◽  
Alloy Formation ◽  
X Ray Diffraction ◽  
Nanocrystalline State ◽  
Compound Formation ◽  
Dsc Studies ◽  
High Energy Ball Mill ◽  
Energy Ball ◽  
Si Content

Fe-Si alloy with a large Si content of 6.5 wt. % is obtained in nanocrystalline state by mechanical alloying of elemental iron and silicon powders. The mechanical alloying process was carried out using a high energy ball mill in argon atmosphere. Samples were collected after 0.5, 1, 2, 4, 6 and 8 hours of ball milling. The X-ray diffraction (XRD) studies indicate that after 4 hours of milling the Fe-Si alloy is formed. The powder magnetisation decreases upon increasing the milling time up to 4 hours as a consequence of the Fe-Si alloy formation. Upon heating, the DSC studies show the Fe3Si compound formation in the samples milled for milling times lower than 6 hours. Also, the Curie temperature of the alloy was evidenced.

Nanocrystalline/Nanosized Mixed Nickel-Manganese Ferrites Obtained by Mechanical Milling

2014 ◽  
Vol 216 ◽  
pp. 243-248
Author(s):  
Ionel Chicinaş ◽  
Traian Florin Marinca ◽  
Bogdan Viorel Neamţu ◽  
Florin Popa ◽  
Olivier Isnard
Keyword(s):  
Mechanical Milling ◽  
High Energy ◽  
Size Analysis ◽  
X Ray Diffraction ◽  
High Energy Ball Mill ◽  
Nanometric Range ◽  
Energy Ball ◽  
The Mean ◽  
Ceramic Route ◽  
Nickel Manganese

A sum of mixed nickel-manganese ferrites, NixMn1-xFe2O4(x=0, 0.3, 0.5, 0.7) were synthesized by classical ceramic route starting from stoichiometric mixtures of commercially MnO2, NiO and Fe2O3. The polycrystalline ferrites obtained by ceramic route were subjected to the mechanical milling procedure in order to reduce the particles size and to refine de crystallites size. A planetary high energy ball mill Fritch Pulverisette 4 was used and the milling time was up to 120 minutes. The ceramic and as-milled ferrites samples were investigated by X-ray diffraction (XRD), scanning electronic microscopy (SEM) and laser particles size analysis (LPSA). After 15 minutes of milling the mean crystallites size for each one of the nickel-manganese ferrites is in nanometric range. After 120 minutes of mechanical milling for all ferrites types the mean crystallites size is at 6-8 nm, depending on Ni/Mn ratio. According to the SEM and LPSA investigations the milled ferrites powders consists in nanometric particles alongside of the micrometric ones. The micrometric particles are formed by multiple nanocrystallites.

Effect of Boron on the Amorphization of Fe-Si Alloys by Mechanical Alloying

2012 ◽  
Vol 730-732 ◽  
pp. 739-744 ◽  
Author(s):  
Petr Urban ◽  
Francisco Gomez Cuevas ◽  
Juan M. Montes ◽  
Jesus Cintas
Keyword(s):  
Electron Microscopy ◽  
Mechanical Alloying ◽  
Alloy System ◽  
High Energy ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Structural And Phase Transformations ◽  
Transmission Electron ◽  
Energy Ball

The amorphization process by mechanical alloying in the Fe-Si alloy system has been studied. High energy ball milling has been applied for alloys synthesis. X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to monitor the structural and phase transformations through the different stages of milling. The addition of amorphous boron in the milling process and the increase of the milling time were used to improve the formation of the amorphous phase. Heating the samples resulted in the crystallization of the synthesized amorphous alloys and the appearance of equilibrium intermetallic compounds.

Phase Transformation in Al3Ni2 Alloy during Mechanical Alloying and Heating of Milling Products

2013 ◽  
Vol 203-204 ◽  
pp. 272-275
Author(s):  
Marek Krasnowski ◽  
Tadeusz Kulik
Keyword(s):  
Mechanical Alloying ◽  
Phase Transformations ◽  
Intermetallic Phase ◽  
Diffraction Method ◽  
High Energy ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
High Energy Ball Mill ◽  
Elemental Powder Mixture ◽  
Energy Ball

An elemental powder mixture corresponding to the Al3Ni2 phase stoichiometry was subjected to mechanical alloying in a high-energy ball mill. Products of this process after various milling times were investigated by differential scanning calorimetry. The phase transformations occurring in the material throughout milling and during heating in a calorimeter were investigated by X-ray diffraction method. This study revealed that a metastable nanocrystalline NiAl intermetallic phase was formed during the mechanical alloying process. Heating of the synthesised powders in the calorimeter caused phase transformations, the product of which was an equilibrium Al3Ni2 intermetallic phase or a mixture of NiAl, Al3Ni2 and Al3Ni intermetallic phases, depending on the milling time and the temperature up to which the material was heated.

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