DSC-TGA Hydrogen Evaluation during Mechanical Milling of AlFe Intermetallic

Fe40Al60 (at%) intermetallic alloy composition was obtained by conventional casting methods and subsequently subjected to high-energy mechanical milling under different conditions of humidity. All samples were characterized by X-ray diffraction patterns (XRD), transmission electron microcopy (TEM) and DSC-TGA thermogravimetric experiments. After the milling process, the amount of hydrogen generated was determined using thermogravimetric analysis and chemical reactions (stoichiometry). All techniques confirm the formation of bayerite phase which is attributed to the hydrogen embrittlement reaction between the intermetallic material and water to release hydrogen. It was observed that the hydrogen generation is increased as the ball milling time is increased. The quantity of hydrogen evaluated is similar to that obtained in previous reported experiments with pure aluminum and some of its alloys.

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

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.922.586 ◽

2014 ◽

Vol 922 ◽

pp. 586-591 ◽

Cited By ~ 1

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.

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Characterization of Ni-CNTs Nanocomposites Produced by Mechanical Alloying

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.829.515 ◽

2013 ◽

Vol 829 ◽

pp. 515-519 ◽

Cited By ~ 4

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.

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Preparation of Y-Ti Bioxides Strengthened Fe-Cr Alloy by Mechanical Milling and Hot Pressing

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.475-476.1307 ◽

2013 ◽

Vol 475-476 ◽

pp. 1307-1310

Author(s):

Lei Dai ◽

Ping Feng ◽

Cai Hua Huang ◽

Guang Wei Zhao

Keyword(s):

Electron Microscope ◽

Hot Pressing ◽

Mechanical Milling ◽

Milling Time ◽

Operating Temperature ◽

Oxide Dispersion Strengthened ◽

X Ray Diffraction ◽

Ferritic Alloys ◽

X Ray ◽

Transmission Electron

Oxide-dispersion-strengthened (ODS) ferritic alloys are fascinating materials for future fusion power reactors due to these materials would allow a substantial increase of the operating temperature. Y-Ti bioxides strengthened Fe-Cr alloy was produced by mechanical milling (MM) followed by hot pressing (HP). Microstructure changes of the mixed powders during mechanical milling and subsequent hot pressing were structurally characterized by means of scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffraction (XRD). The observations of structure of the mixed powders after MM indicated that the powders are fractured and welded with rotation and vibration of container during mechanical milling. And the particle size decreases with increasing milling time. Nanoscale Y-Ti bioxides were formed during the HP process.

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Thermal and Structural Characterization of Nanocomposite Iron Nitride - Alumina and Iron Nitride - Silica Particles

MRS Proceedings ◽

10.1557/proc-703-v9.16 ◽

2001 ◽

Vol 703 ◽

Author(s):

Ann M. Viano ◽

Sanjay R. Mishra

Keyword(s):

Particle Size ◽

Milling Time ◽

Iron Nitride ◽

X Ray Diffraction ◽

X Ray ◽

Thermal Peak ◽

Transmission Electron ◽

Diffraction Patterns ◽

The One

ABSTRACTNanocomposite iron nitride based powders are known to have enhanced magnetic and other physical properties. To further explore their potential for application in various fields, we have performed a systematic study of the iron nitride - alumina and iron nitride - silica systems. Iron nitride powder of composition FexN (2 < x < 4), containing both Fe3N and Fe4N phases, was mechanically milled with Al2O3 or SiO2 powder for 4, 8, 16, 32, and 64 hours at the following compositions; (FexN)0.2(Al2O3)0.8, (FexN)0.6(Al2O3)0.4, (FexN)0.2(SiO2)0.8, and (FexN)0.6(SiO2)0.4. Differential thermal analysis and X-ray diffraction were performed to investigate thermal and structural transitions as a function of milling time. As the milling time is increased, the thermal peak corresponding to Fe4N is diminished, while the one corresponding to Fe3N is enhanced. These transitions are correlated with X-ray diffraction patterns. All XRD peaks broaden as a function of milling time, corresponding to smaller particle size. Transmission electron microscopy also reveals a decrease in particle size as the milling time in increased.

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Phase Amorphization during High-Energy Milling of Mixtures of Zirconia with Yttria or Ceria Powders

Materials Science Forum ◽

10.4028/www.scientific.net/msf.498-499.331 ◽

2005 ◽

Vol 498-499 ◽

pp. 331-336 ◽

Cited By ~ 2

Author(s):

R. Muccillo ◽

L. Franchi ◽

J.T. Santos ◽

I.C. Cosentino ◽

E.N.S. Muccillo

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Barium Carbonate ◽

High Energy ◽

Milling Process ◽

X Ray Diffraction ◽

X Ray ◽

High Energy Milling ◽

Transmission Electron ◽

Strontium Ferrites

Strontium ferrites powders were obtained by high energy milling process after calcinations of iron oxide and barium carbonate. Phase formations and crystallite size was determined using X-ray diffraction. Morphology, particle size and agglomeration stages were analyzed using scanning and transmission electron microscopy. Results show particles in the range of 14 to 40 nanometers, large agglomerates and crystalline phases formation.

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Synthesis of the Nanocrystalline/Nanosized NiFe2O4 Powder by Ceramic Method and Mechanical Milling

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.188.27 ◽

2012 ◽

Vol 188 ◽

pp. 27-30 ◽

Cited By ~ 1

Author(s):

Vasile Florin Tarța ◽

Ionel Chicinaş ◽

Traian Florin Marinca ◽

Bogdan Viorel Neamţu ◽

Florin Popa ◽

...

Keyword(s):

Milling Time ◽

High Energy ◽

Milling Process ◽

X Ray Diffraction ◽

Polycrystalline Nickel ◽

Powder Morphology ◽

Chemical Homogeneity ◽

Ceramic Method ◽

X Ray ◽

Nanometric Range

The polycrystalline nickel ferrite - NiFe2O4has been obtained by ceramic route starting from a stoichiometric mixture of oxides (NiO and α-Fe2O3powders). The obtained NiFe2O4was subjected to high energy ball milling. The formation of NiFe2O4by ceramic method and also the evolution of the powder during milling were studied by X-ray diffraction. The mean crystallite size of the NiFe2O4continuously decreases with the increasing of the milling time and for all the milling time it is in nanometric range. The particles sizes are drastically reduced by milling process. For the milled samples, the particles size is ranging from tens of microns to few nanometers. The powder morphology and local chemical homogeneity were investigated by scanning electron microscopy (SEM) and respectively by energy dispersive x-ray spectrometry (EDX).

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Modification of the Structural Characteristics of the Tungsten Powder through Short Mechanical Milling Processes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.672.255 ◽

2011 ◽

Vol 672 ◽

pp. 255-258

Author(s):

Dana Salomie ◽

Nicolae Jumate

Keyword(s):

Fine Structure ◽

Mechanical Milling ◽

Structural Characteristics ◽

Tungsten Powder ◽

High Energy ◽

Milling Process ◽

Planetary Mill ◽

X Ray Diffraction ◽

Process Duration ◽

X Ray

The objective of this study is to improve the sintering of W powder through increasing the density of the crystalline structure imperfections. The powder of W was processed by short processes of mechanical milling in a high energy planetary mill. The paper presents the influence of mechanical milling process duration upon the modifications of the structural characteristics of W powder. The fine structure has been studied by using X-ray diffraction.

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Preparation and Crystallization of Nd2Fe14B/α-Fe Permanent Magnetic Nanomaterial by Mechanical Milling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.486.70 ◽

2012 ◽

Vol 486 ◽

pp. 70-74

Author(s):

Yong Ping Jin ◽

Ming Hu ◽

Jin Gao

Keyword(s):

Grain Size ◽

Mechanical Milling ◽

Milling Time ◽

Cast Alloy ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Crystallization Effect ◽

Magnetic Nanomaterial ◽

Higher Temperature

Nanocomposite Nd2Fe14B/α-Fe magnetic material had been prepared by mechanical milling Nd8Fe86B6 as-cast alloy in Argon and subsequent crystallization. Effect of mechanical milling and crystallization technique on its structure had been investigated by means of X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM) and Differential Scanning Caborimetry (DSC), etc. The crystallization behavior of amorphous Nd8Fe86B6 powders had also been studied. The results showed that Nd2Fe14B grain refined quickly and the grain size of α-Fe decreased while extending milling time. After milling for 25h, grain size of α-Fe reached a constant (about 7nm). Higher temperature of complete crystallization as well as finer and more homogeneous grains resulted from longer milling time. During the process of crystallization, the total amorphous phase crystallized into four phases firstly, i.e., Nd4.4Fe77.8B17.8, Nd1.1Fe4B4, Nd2Fe14B and α-Fe. At higher temperature, final mixture was consisted of Nd2Fe14B, α-Fe and a few undecomposed Nd1.1Fe4B4 phase.

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Structural, Optical, and Photocatalytic Properties of ZnSe Nanoparticles Influenced by the Milling Time

Crystals ◽

10.3390/cryst11091125 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1125

Author(s):

Bui Thi Thu Hien ◽

Vu Thanh Mai ◽

Pham Thi Thuy ◽

Vu Xuan Hoa ◽

Tran Thi Kim Chi

Keyword(s):

Raman Spectra ◽

Milling Time ◽

Blue Emission ◽

Near Band Edge ◽

X Ray Diffraction ◽

Znse Nanoparticles ◽

X Ray ◽

Transmission Electron ◽

Diffraction Patterns ◽

Average Size

ZnSe nanoparticles (NPs) were prepared by combining both hydrothermal and mechanical milling methods. Transmission electron microscopy images show that fabricated ZnSe NPs with a sphere-like shape have an average size (d) in the range of 20–100 nm, affected by changing the milling time from 10 to 60 min. All the samples crystalize in zincblende-type structure without impurities, as confirmed by analyzing X-ray diffraction patterns, Raman spectra, and energy-dispersive X-ray spectroscopy. Carefully checking Raman spectra, we have observed the broadening and redshift of vibration modes as decreasing NP size, which are ascribed to extra appearance of disorder and defects. The photoluminescence study has found a blue emission at 462 nm attributed to the excitonic near-band edge and a broad defect-related emission around 520–555 nm. Increasing milling time leads to the decrease in the exciton-emission intensity, while the defect-related emissions increase gradually. Interestingly, as decreasing d, we have observed an improved photodegradation of Rhodamine B under UV irradiation, proving application potentials of ZnSe NPs in photocatalytic activity.

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