Evaluation of Tribological Properties of Organoclay Reinforced UHMWPE Nanocomposites

2016 ◽  
Vol 139 (1) ◽  
Author(s):  
Abdul Samad Mohammed ◽  
Annas bin Ali ◽  
Merah Nesar
Keyword(s):  
Tribological Properties ◽  
Large Scale ◽  
Ultrahigh Molecular Weight Polyethylene ◽  
High Energy ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Uniform Dispersion ◽  
Ultrahigh Molecular Weight ◽  
Energy Ball

The current study is aimed to investigate the tribological properties of ultrahigh molecular weight polyethylene (UHMWPE) reinforced with organoclay Cloisite (C15A). Nanocomposites are prepared using a high energy ball milling process followed by hot pressing. Three different loadings of 0.5 wt.%, 1.5 wt.%, and 3 wt.% of C15A, respectively, are used as reinforcement. Results from the ball-on-disk wear tests showed that nanocomposites reinforced with 1.5 wt.% of C15A exhibited best wear resistance and lower coefficient of friction (COF), with C15A reducing the wear rate by 41% and the COF by 38%, when compared to the pristine UHMWPE. These improvements are attributed to the uniform dispersion of the nanosized clay platelets preventing large-scale material removal and formation of a thin tenacious, continuous transfer film on the counterface for C15A organoclay composites. X-ray diffraction (XRD), scanning electron microscopy (SEM), and optical profilometry are used to characterize the morphology of the nanocomposites and the wear tracks. SEM images of worn surfaces indicated more abrasive wear for the case of pristine UHMWPE as compared to organoclay composites.

Microstructure and Oxidation Resistance of Mechanically Alloyed and Sintered Ni-Nb and Ni-Nb-Ta Alloys

2017 ◽  
Vol 899 ◽  
pp. 19-24
Author(s):  
Lucas Moreira Ferreira ◽  
Stephania Capellari Rezende ◽  
Antonio Augusto Araújo Pinto da Silva ◽  
Gael Yves Poirier ◽  
Gilberto Carvalho Coelho ◽  
...  
Keyword(s):  
Ball Milling ◽  
Oxidation Resistance ◽  
Energy Dispersive Spectrometry ◽  
High Energy ◽  
Milling Process ◽  
Ternary Alloys ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
Static Oxidation ◽  
Energy Ball

The present work reports on the microstructure and oxidation resistance of Ni-25Nb, Ni-20Nb-5Ta and Ni-15Nb-10Ta alloys produced by high-energy ball milling and subsequent sintering. The sintered samples were characterized by optical microscopy, scanning electron microscopy, X-ray diffraction, energy dispersive spectrometry, and static oxidation tests. Homogeneous microstructures of the binary and ternary alloys indicated the major presence of the β-Ni3Nb compound as matrix, which dissolved large amounts of tantalum. Consequently, the β-Ni3Nb peaks moved toward the direction of smaller diffraction angles. Iron contamination lower than 6.7 at.-% was detected by EDS analysis, which were picked-up during the previous ball milling process. After the static oxidation tests (1100°C for 4 h) the sintered Ni-25Nb, Ni-20Nb-5Ta and Ni-15Nb-10Ta alloys presented mass gains of 31.5%, 30.5% and 28.8%, respectively. Despite the higher densification of the Ni-15Nb-10Ta alloy, the results suggested that the tantalum addition contributed to improve the oxidation resistance of the β-Ni3Nb compound.

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.

CuAl2 Intermetallic Alloy Subjected to the Hydrogen Embrittlement Reaction by Using Mechanical Attrition in Water

2014 ◽  
Vol 793 ◽  
pp. 29-35 ◽  
Author(s):  
Ares G. Hernández-Torres ◽  
F. Mares-Briones ◽  
J.R. Romero-Romero ◽  
G. Rosas
Keyword(s):  
Hydrogen Embrittlement ◽  
High Energy ◽  
Milling Process ◽  
Reaction Products ◽  
X Ray Diffraction ◽  
Aluminum Hydroxides ◽  
Intermetallic Materials ◽  
Mechanical Attrition ◽  
Energy Ball ◽  
Theoretical Amount

Al based intermetallic materials are commonly susceptible to hydrogen embrittlement reaction. Water vapor in the air reacts with the aluminum in the alloy and releasing hydrogen. Thus, the aid of this work is to know how much hydrogen can be released when the embrittlement reaction is induced inside the milling container. For this purpose the CuAl2intermetallic material was made by conventional castings methods and then subjected to high-energy ball milling in water. The samples were characterized by X-ray diffraction pattern, attenuated total reflectance spectroscopy and scanning electron microscopy (SEM). After the milling process, the amount of hydrogen released was correlated with the other reaction products obtained during the reaction. These products were primarily aluminum hydroxides. The amount of hydrogen that can be released is similar to the theoretical amount possible that can be released.

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.

Nanostructure Evolution of Expanded Graphite during High-Energy Ball-Milling

2011 ◽  
Vol 80-81 ◽  
pp. 229-232 ◽  
Author(s):  
Wen Yan Duan
Keyword(s):  
Expanded Graphite ◽  
High Energy ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Natural Graphite ◽  
Air Atmosphere ◽  
Out Of Plane ◽  
Crystallite Sizes ◽  
Energy Ball ◽  
Diffraction Patterns

Expanded graphite (EG) was ball-milled in a high-energy planetary-type mill under an air atmosphere. The X-ray diffraction patterns of the products show that during the milling process (up to 100 h), the out-of-plane (Lc) and in-plane (La) crystallite sizes decrease gradually from 15.4 to 11.3 nm and 24.1 to 15.5 nm, respectively. The value of Lc/La, which is used to estimate the shape of the crystallites, increases gradually from 0.64 to 0.73. Compared with most of natural graphite, this Lc decrease degree of EG is far lower. This increased value of Lc/La indicates that the crystallites of the milled EG become thicker and steeper, which is contrary to the case for natural graphite.

Luminescent Properties of Eu3+-Doped BaGd2ZnO5 Phosphors for White LED

2012 ◽  
Vol 531-532 ◽  
pp. 22-26 ◽  
Author(s):  
Hyeon Mi Noh ◽  
Hyun Kyoung Yang ◽  
Byung Kee Moon ◽  
Byung Chun Choi ◽  
Jung Hyun Jeong ◽  
...  
Keyword(s):  
Sintering Temperature ◽  
Emission Spectra ◽  
Luminescent Properties ◽  
High Energy ◽  
White Led ◽  
Photoluminescence Properties ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Milling Method ◽  
Energy Ball

BaGd2ZnO5:Eu3+ phosphors were synthesized at sintering temperatures of 800, 900, 1000, 1100 and 1200 °C by high-energy ball milling method. The crystallinity, surface morphology and photoluminescence properties of phosphors were investigated by using X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and luminescence spectrophotometry, respectively. The XRD results indicate that the crystallinity of the powder was improved and the powder shows a orthorhombic structure as the sintering temperature increased. The emission spectra of BaGd2ZnO5phosphors excited at 280 nm exhibit a series of shaped peaks assigned to the5D0→7FJ(J=0, 1, 2, 3) transitions, and luminescence intensity was increased with increasing sintering temperature. The FE-SEM images indicate that the size and shape of particles are regular.

Synthesis of the Fe-10%Si Nanocrystalline Powder by Mechanical Alloying

2014 ◽  
Vol 216 ◽  
pp. 283-287 ◽  
Author(s):  
Cristina Daniela Stanciu ◽  
Traian Florin Marinca ◽  
Florin Popa ◽  
Ionel Chicinaş ◽  
Olivier Isnard
Keyword(s):  
Mechanical Alloying ◽  
High Energy ◽  
Milling Process ◽  
Nanocrystalline Powder ◽  
Alloy Formation ◽  
X Ray Diffraction ◽  
Nanocrystalline State ◽  
High Energy Ball Mill ◽  
Energy Ball ◽  
Si Content

Fe-Si alloy with a Si content of 10 wt. % was obtained in nanocrystalline state by mechanical alloying of elemental iron and silicon powders. The mechanical alloying process was carried out in a high energy ball mill (Fritsch, Pulverisette 4) in argon atmosphere. The X-ray diffraction (XRD) studies indicated that after 4 hours of milling the Fe-Si alloy is formed. The mean crystallites size decreases down to 7 nm after 8 hours of milling. The particles morphology investigated by scanning electron microscopy (SEM) showed an evolution during milling process from two different kinds of particles to a one kind of particles with irregular shape. The magnetisation of powders decreases upon increasing the milling time up to 4 hours as a consequence of the Fe-Si alloy formation.

scholarly journals The effect of ball milling on crystallite size

2020 ◽  
Vol 3 (1) ◽  
pp. 543-549
Author(s):  
Oguzhan Sahin ◽  
Veysel Erturun
Keyword(s):  
Crystallite Size ◽  
Ball Milling ◽  
High Energy ◽  
Metal Powders ◽  
X Ray Diffraction ◽  
Ceramic Powders ◽  
Sem Images ◽  
X Ray ◽  
Sic Ceramic ◽  
Energy Ball

Homogeneous mixing of Al, varying amounts of Cu, Mg and Zn metal powders and SiC ceramic powders and mechanical alloys of metal powders by using high energy ball milling were carried out in the Retsch MM400 model mixer device, which performs movement in a spex manner. After this process, X-ray diffraction (XRD) was applied to the powdered mixtures. With the data obtained from XRD graphics; The crystallite size was calculated using the Scherrer equation, and the lattice stresses were calculated using the Williamson-Hall equation and comparisons between these two data were made. It was observed that the amount of Cu by weight, both the crystallite size, did not make a notable change for this property. Then, powder mixtures were sintered in hot isostatic press in argon atmosphere, which is a shielding gas, and turned into samples. These samples were polished and scanning electron microscopy (SEM) images were taken.

Obtention of Aluminium-Quasicrystal Composites by Mechanical Alloying

2012 ◽  
Vol 727-728 ◽  
pp. 281-286
Author(s):  
Fernando Luís Vieira de Sousa ◽  
Pedro Cordeiro Romio ◽  
Tibério Andrade Passos ◽  
Severino Jackson Guedes de Lima
Keyword(s):  
Mechanical Alloying ◽  
Large Scale ◽  
High Energy ◽  
X Ray Diffraction ◽  
New Techniques ◽  
Average Hardness ◽  
Hardness Tests ◽  
Energy Ball ◽  
Object Of Study ◽  
Do So

The quasicrystals materials possess a combination of unusual properties, since they present a long range ordered atomic structure, which is not periodic. Because of this, these materials have been object of study of many researchers in the last few years. Currently, the research is focused on determining new techniques able to produce these materials in a large scale, as well as finding new utilities. One of the ways to do so, is to use quasicrystals as coating; another way is the fabrication of composites. In this paper, aluminum composites with the strengthening of quasicrystalline particles from the alloy Al59,2Cu25,5Fe12,3B3 in volumetric fractions of 6% to 20% were developed by high energy ball milling. The powders obtained by mechanical alloying was compacted at 300MPa, sintered and submitted to micro hardness tests. The characterization was made by X-ray diffraction and SEM. In the grinding we used a 2² factorial design with factors time and speed, and the hardness of composite as response. The specimens had an average hardness of 25.75GPa for reinforcement with 6% QC and 34.75GPa for reinforcement of 20% QC.

scholarly journals Investigation of the Reaction between Fe2O3 and Si Activated by Ball Milling

1996 ◽  
Vol 51 (8) ◽  
pp. 915-922 ◽  
Author(s):  
Giorgio Concas ◽  
Francesco Congiu ◽  
Anna Corrias ◽  
Carlo Muntoni ◽  
Giorgio Paschina ◽  
...  
Keyword(s):  
Ball Milling ◽  
Oxygen Transfer ◽  
Amorphous Matrix ◽  
High Energy ◽  
Milling Process ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Intermediate Phases ◽  
Energy Ball

Abstract The path of the reaction between Fe2O3 and Si, activated by high energy ball milling, has been investigated by X-ray diffraction and Mössbauer spectroscopy. Hematite reduction involves oxygen transfer from Fe to Si with the formation of intermediate phases containing Fe(II), which are then reduced to Fe(0). A steady state is reached in the milling process where the reduction of stoichiometric amounts of Fe2O3 and Si is not complete and an amount of Fe(II) in an amorphous matrix still remains. The same intermediate compounds are also observed in the milling process of mixtures with higher Fe2O3 /Si molar ratio.

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