Effect of fluorine and chlorine ions on the reaction sintering of mechanically activated zircon-alumina mixture Ceramics – Silikty 59 (3) 216-219 (2015) 219 Powder morphology Figure 3 shows the SEM micrographs of the 20 h ball-milled powders As can be seen in the presence of ammonium fluoride and ammonium chloride larger The starting material consisted of Mn 54 Al 46 powders produced by gas-atomization under argon with 0 4 at % composition Further details of gas-atomized particles preparation have been published elsewhere [19 20] Mn 54 Al 46 powders were milled by surfactant-assisted (oleic acid) mechanical milling for different times (30–270 s) in order to reduce possible oxidation

Significant improvement of Jc in MgB2 bulk superconductor

powders with/without ball milling and amorphous boron precursor powder As expected crystalline boron powders without ball milling have a crystalline structure with space group R3m After ball milling the crystalline phase still remains in the powders Broadening of the peaks can be observed in the ball-milled crystalline boron powders The

Vol 48 No 1 June 2015 pp 37-44 37 Facile synthesis of copper oxide nanoparticles using copper hydroxide by mechanochemical process Heydar Khadivi Ayask* Jalil Vahdati Khaki Mohsen Haddad Sabzevar Department of Materials Science and Metallurgical Engineering Engineering Faculty Ferdowsi University of Mashhad

About 0 35 g of powders ball-milled for 20 h were heated under argon in a Netzsch 404 differential scanning calorimeter (DSC) at a rate of 20 C/min from 25 C to desired temperatures and then naturally cooled to the ambient temperature The heated powders were

These elemental powders were initially milled using zirconia balls The aCuSe phase was present in all of the milled powders because of the mechanical alloying effect between the Cu and Se powders The solid state reaction mechanism was examined for the synthesis process The phase analysis suggested that the Cu2ZnSnSe4 powder crystallized into

powders were milled for 1 2 4 8 16 and 24 hours in a ZOZ high energy mill at 400 rpm and with a ball to powder ratio of 10:1 Milling was done in gaseous nitrogen The particle size morphology grain size and phase constituents of the milled powders were determined as a function of the milling time A CILAS particle size analyzer was used

Silver

Silver-zinc oxide electrical contact materials by mechanochemical synthesis route P B Joshi 1 V J Rao 1 B R Rehani 1 Arun Pratap 2 1Department of Metallurgical Engineering M S University of Baroda Vadodara 390 001 2Department of Applied Physics M S University of Baroda Vadodara 390 001 2E-mail: apratapmsuyahoo

High-energy milled powders composed of a-silicon nitride yttrium oxide and aluminum oxide with metallic aluminum were analyzed with powder XRD Peak height of silicon nitride decreased and peaks of yttrium oxide and metallic aluminum diminished The peak height of β-silicon nitride decreased with increasing of ball/powder ratio in high energy

Received 13 July 2001 accepted for publication 7 November 2001 White-colored materials synthesized by a thermal annealing of milled GaN powders at 930 C in a nitrogen atmosphere were identified to be monoclinic ␤ -Ga2 O3 nanowires by x-ray diffraction and scanning electron microscopy High-resolution transmission electron microscopy

Nanocrystalline zinc ferrite ZnFe2O4 powders were successfully synthesized only by milling for 30 hours The X-ray diffraction spectrum of the as-milled powders (without heating) showed twelve ZnFe2O4 peaks and four weak peaks of coexisting unreacted Fe2O3 The crystallite size of the mechanochemicallysynthesized ZnFe2O4 was 26 3 nm Evidence

obtained from milled and 800C annealed W [14] W ˚ milled and annealed at 730˚C [16] milled W-Ni powder mixture annealed at 730˚C and 1400˚C [16] as well as from mixture of separately milled elemental Co and W powders compacted and annealed at 800˚C [14] The corresponding formation mechanisms were also provided

DTA run 30 to 40 mg of powders were hermetically sealed has been also observed in other alloy systems [8 9] After 64 8 in a ceramic pan to allow a temperature excursion to 1223 K ks of milling new diffraction peaks appeared (Figure 1) After mechanical alloying the ball-milled powders were determined to be a result of the in-situformation

the diffraction profile peaks D is the crystallite size ε is the microstrain λ is the X-ray wavelength and θ is the Bragg angle To confirm the crystallite size obtained by XRD the microstructure of the milled powders was also (TEM) TEM observations were carried out on a Tecnai G2 F20 transmission electron microscopy operating at an acceleration voltage of 200 kV Particle size

J S Luo H G Lee and S N Sinha: Microstructure and superconducting properties of attrition-milled of Bragg peaks can be attributed to both diminished particle size and atomic-level15 strain '16 It is interesting to note that the relative intensity of the (002) peak decreases much more rapidly than those of other Bi-

Microstructure characterization and hydrogen desorption

Abstract: Microstructure and phase evolutions of Mg−Al powders ball milled in hydrogen atmosphere were investigated Both in Mg−3%Al (mass fraction) and Mg−9%Al systems β-MgH2 phase was observed upon a short milling time of 4 h and its maximum content of ~80% was reached after 32 h

FULL LENGTH ARTICLE Influence of precursor calcination temperature on sintering and conductivity of Li1 5Al0 5Ti1 5(PO4)3 ceramics Masashi Kotobuki and Masaki Koishi Department of Material and Environmental Engineering Hakodate National College of

Effect of thermal treatment on mechanically deformed cobalt powder A S Bolokangab M J Phashaa S T Camagua D milled and mixture of unmilled and milled powders were cold pressed at a pressure of 20 MPa to form cylindrical compacts of 17mm in diameter and 2 mm in thickness These compacts were sintered in a Xeron vacuum furnace at temperature of

milled powders at various milling times was presented in Fig 1 Before milling the strong diffraction peaks for Ti and SiC phases were observed After 5h of milling although the Ti and SiC peaks were still well detected the peaks were broadened and weak in intensity The identified diffraction peaks of powders above 10h of

Synthesis of nanomaterials by a simple low cost and in high yield has been a great challenge since the very early development of nanoscience Various bottom and top down approaches have been developed so far for the commercial production of nanomaterials Among all top down approaches high energy ball milling has been widely exploited for the synthesis of various

Figure 2 the particle size distribution of the as‐milled BBNO powders is characterized by three peaks at approximately 0 25 0 95 and 5 5 m with 0 95 m being the dominant par-ticle size The inset of Figure 2 shows a typical SEM image of the as‐milled BBNO powders which indicates an irregular