scholarly journals Preparation and Evaluation of Cu-Zn-GNSs Nanocomposite Manufactured by Powder Metallurgy

Crystals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1449
Author(s):  
A. T. Hamed ◽  
E. S. Mosa ◽  
Amir Mahdy ◽  
Ismail G. El-Batanony ◽  
Omayma A. Elkady
Keyword(s):  
Ball Milling ◽  
Weight Ratio ◽  
High Energy ◽  
Control Agent ◽  
Homogeneous Microstructure ◽  
Mechanical And Tribological Properties ◽  
Zn Content ◽  
Copper Zinc ◽  
Energy Ball ◽  
Ball Milling Technique

Room-temperature ball milling technique has been successfully employed to fabricate copper-zinc graphene nanocomposite by high-energy ball milling of elemental Cu, Zn, and graphene. Copper powder reinforced with 1-wt.% nanographene sheets were mechanically milled with 5, 10, 15, and 20 wt.% Zn powder. The ball-to-powder weight ratio was selected to be 10:1 with a 400-rpm milling speed. Hexane and methanol were used as a process control agent (PCA) during composite fabrication. The effect of PCA on the composite microstructure was studied. The obtained composites were compacted by a uniaxial press under 700 MPa. The compacted samples were sintered under a controlled atmosphere at 1023 K for 90 min. The microstructure, mechanical, and tribological properties of the prepared Cu-Zn GrNSs nanocomposites were studied. All results indicated that composites using hexane as PCA had a uniform microstructure with higher densities. The densities of sintered samples were decreased gradually by increasing the Zn percent. The obtained composite contained 10 wt.% Zn had a more homogeneous microstructure, low porosity, higher Vickers hardness, and compression strength, while the composite contained 15 wt.% Zn recorded the lowest wear rate. Both the electrical and thermal conductivities were decreased gradually by increasing the Zn content.

Synthesis by High-Energy Ball Milling of MgH2-TiFe Composites for Hydrogen Storage

2017 ◽  
Vol 899 ◽  
pp. 13-18 ◽  
Author(s):  
Ricardo Mendes Leal Neto ◽  
Rafael de Araújo Silva ◽  
Ricardo Floriano ◽  
Graziele Cristina Seco Coutinho ◽  
Railson Bolsoni Falcão ◽  
...  
Keyword(s):  
Ball Milling ◽  
Hydrogen Absorption ◽  
Hydrogen Desorption ◽  
High Energy ◽  
Control Agent ◽  
High Energy Ball Milling ◽  
Absorption Kinetics ◽  
Particle Size Reduction ◽  
Milled Sample ◽  
Energy Ball

The aim of this work is to investigate the influence of some processes variables on the microstructure and hydrogen absorption kinetics of MgH2 - X wt.% TiFe composites. Samples were synthesized by high-energy ball milling in a planetary (X = 40, 50, 60) and shaker mill (X = 40) under high-purity argon atmosphere. Commercial MgH2 instead of Mg powder was used in order to reduce adherence on the vial and balls. TiFe powder was previously produced by ball milling a mixture of TiH2 and Fe powders followed by a reaction synthesis at 600oC. Milled composites samples were characterized by XRD and SEM analysis. Milling time was preliminary investigated (X = 40) in the planetary ball mill (6 to 36h). TiFe particle size reduction was shown to be difficult since they are surrounded by MgH2 matrix. Strong particle reduction was obtained by using a shaker mill only for 2 hours and adding cyclohexane as process control agent. No reaction between MgH2 and TiFe compound was observed in any milled sample. Hydrogen absorption kinetics measurements of the as-milled samples were conducted on an Sieverts' type apparatus at room temperature after hydrogen desorption at 350oC under vacuum. The best hydrogen kinetics (3 wt% at the first hour) was attained by the planetary milled sample (36 h). Higher hydrogen capacity was observed for the sample milled in the shaker mill (4.0 wt.%), but only after 13h.

Investigations on the Structural, Optical and Dielectric Properties of Ball-Milled ZnO–Fe2O3 Nanocomposites

2020 ◽  
Vol 19 (04) ◽  
pp. 1950034
Author(s):  
V. Balachandar ◽  
J. Brijitta ◽  
K. Viswanathan ◽  
R. Sampathkumar
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Ball Milling ◽  
High Energy ◽  
X Ray Diffraction ◽  
Dielectric Constant And Loss ◽  
Energy Ball ◽  
Uv Visible ◽  
Ball Milling Technique ◽  
Xrd Patterns

In this study, ZnO–Fe2O3 nanocomposites were prepared by high-energy ball milling technique and characterized through X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), UV–visible spectroscopy and dielectric spectroscopy. The amount of Fe2O3 in the ZnO–Fe2O3 nanocomposites was varied at the rates of 1[Formula: see text]wt.%, 3[Formula: see text]wt.% and 5[Formula: see text]wt.% in order to investigate its influence on the structural, optical and dielectric properties of the nanocomposites. XRD patterns of nanocomposites revealed no shift in peak positions and hence confirmed the formation of composites after ball milling. Further, it was observed from FESEM analysis that Fe2O3 particles were distributed randomly on the ZnO matrix of the nanocomposites. ZnO–Fe2O3 nanocomposites reveal extended optical absorption in the range of 400–600[Formula: see text]nm from UV studies. The dielectric constant and loss of the nanocomposites decrease exponentially with increase in frequency. The composition and frequency dependences of the dielectric constant, dielectric loss and AC conductivity are explained based on the Maxwell–Wagner effect and Koop’s theory.

Effects of iron impurities in mechanical alloying using steel media

1993 ◽  
Vol 8 (2) ◽  
pp. 239-241 ◽  
Author(s):  
P.J. Yvon ◽  
R.B. Schwarz
Keyword(s):  
Mechanical Alloying ◽  
Ball Milling ◽  
High Energy ◽  
High Energy Ball Milling ◽  
Metastable Phases ◽  
Iron Contamination ◽  
Energy Ball ◽  
Ball Milling Technique

Mechanical alloying, a high-energy ball-milling technique, is now widely used for preparing alloy powders with metastable phases (crystalline or amorphous). The technique, however, may contaminate the powder with material eroded from the vial and milling media. We report on the analysis and effects of iron contamination on Al25Ge75 powders that we prepared by mechanically alloying mixtures of aluminum and germanium powders, using different mechanical alloying apparatuses.

scholarly journals Structural and Magnetic Properties of Ba3[Cu0.8−xZnxMn0.2]2Fe24O41 Z-Type Hexaferrites

2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Eman S. Al-Hwaitat ◽  
Sami H. Mahmood ◽  
Mahmoud Al–Hussein ◽  
Ibrahim Bsoul
Keyword(s):  
Magnetic Properties ◽  
Anisotropy Field ◽  
High Energy ◽  
X Ray Diffraction ◽  
Zn Content ◽  
Energy Ball ◽  
Structural And Magnetic Properties ◽  
Ball Milling Technique ◽  
Xrd Patterns

We report on the synthesis and characterization of Ba3[Cu0.8−xZnxMn0.2]2Fe24O41 (x = 0.0, 0.2, 0.4, 0.6, and 0.8) barium hexaferrites. The samples were prepared by high-energy ball-milling technique and double-sintering approach. The effects of Zn substitution for Cu on the structural and magnetic properties of the prepared samples were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM). XRD patterns of the samples revealed the presence of a major Z-type hexaferrite phase, together with secondary M-type and Y-type phases. The magnetic results indicated that the saturation magnetization increased slightly with increasing the Zn content, while the coercivity and magnetocrystalline anisotropy field exhibited a decreasing tendency with the increase of Zn content. The thermomagnetic curves revealed the complex magnetic structure of the prepared samples and confirmed that the Curie temperature of the magnetic phases decreased with increasing x as a result of the reduction of the strength of the superexchange interactions.

The Study of Hydrogen Sorption Properties of Mg17Al12La0.45

2011 ◽  
Vol 311-313 ◽  
pp. 1351-1356
Author(s):  
Li Juan Pang ◽  
Yun Gui Chen ◽  
Chao Ling Wu ◽  
Xue Feng Zhang ◽  
Gang Deng
Keyword(s):  
Ball Milling ◽  
Hydrogen Desorption ◽  
High Energy ◽  
Milling Process ◽  
High Energy Ball Milling ◽  
Sorption Properties ◽  
Hydrogen Sorption ◽  
Ball Milling Process ◽  
Energy Ball ◽  
Ball Milling Technique

Mg17Al12and rare earth improved Mg17Al12La0.45alloys were prepared by resistance melting method. The hydrogen sorption properties of the alloys with and without ball-milling process were investigated with the help of PCT measurements. The phase compositions of the experimental alloys were determined through powder X-Ray diffraction. It is found that the introduction of La and the high energy ball-milling technique could remarkably improve the hydrogen sorption capability of Mg17Al12. For Mg17Al12La0.45alloy, the hydrogen absorption starts at 473K and the hydridying rate increases at each temperature (573K, 523K, 473K) after high energy ball-milling process. The hydrogen desorption capacity of this alloy is 4wt% at 573K. XRD shows that there are two phases Mg17Al12and Al2La0.15Mg0.85after melting and Al2La0.15Mg0.85phase always exists during hydrogen sorption cycles of Mg17Al12La0.45.

scholarly journals Environmentally friendly nanocrystalline magnesium hydride decorated with metallic glassy-zirconium palladium nanopowders for fuel cell applications

RSC Advances ◽  
2019 ◽  
Vol 9 (48) ◽  
pp. 27987-27995 ◽  
Author(s):  
M. Sherif El-Eskandarany ◽  
Mohammad Banyan ◽  
Fahad Al-Ajmi
Keyword(s):  
Fuel Cell ◽  
Solid State ◽  
Hydrogen Storage ◽  
Ball Milling ◽  
Storage System ◽  
High Energy ◽  
Magnesium Hydride ◽  
Hydrogen Storage System ◽  
Energy Ball ◽  
Ball Milling Technique

A new solid-state hydrogen storage system of magnesium hydride (MgH2) doped with 5 wt% of metallic glassy (MG) zirconium palladium (Zr2Pd) nanopowder was fabricated using a high-energy ball milling technique.

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