Influences of Ball-Milling Time on Gas-Sensing Properties of ZnO-WO3 Nanocomposites

2011 ◽  
Vol 324 ◽  
pp. 141-144 ◽  
Author(s):  
Ahmad Al Mohammad ◽  
Fatemh Maksoud
Keyword(s):  
Pore Size ◽  
Ball Milling ◽  
Milling Time ◽  
Size Range ◽  
Gas Sensing ◽  
High Energy ◽  
Sensor Response ◽  
High Energy Ball Mill ◽  
Gas Sensing Properties ◽  
Energy Ball

The relevance of sensor response to NO2 with the nanostructure of the sensing body was investigated for thick-film devices using ZnO(WO3) nanocomposites. When the nanocomposites was prepared from constituent oxides by milling in a high energy ball mill for various spans of time (1–21 h), the sensor response to 100 ppm NO2, defined as the ratio of the electrical resistance in air to that in the sample gas, was found to reach a maximum as large as about 80 at 21 h of high energy ball-milling (HEBM). XRD and SEM observations of the granular state and pore size distribution analyses indicated that increasing HEBM time gave rise especially to an increase in the volume of pores in the pore size range of 20–35 nm. It is suggested that such a change in nanostructure is responsible for the marked promotion of the response to NO2. For comparison, the response to NO2 of ZnO or WO3 nanoparticles prepared by an HEBM method was also presented. In this case, the response to NO2 can be 10 times larger at HEBM for 21 h.

Microstructure and Characteristics of Ti-Nb-Sn-HA Composite Powder Fabricated by Mechanical Alloying

2011 ◽  
Vol 55-57 ◽  
pp. 886-891
Author(s):  
Xiao Peng Wang ◽  
Shu Long Xiao ◽  
Yu Yong Chen ◽  
Zhi Guang Liu ◽  
Kee Do Woo
Keyword(s):  
Ball Milling ◽  
Milling Time ◽  
Milled Powder ◽  
High Energy ◽  
Composite Powders ◽  
Β Phase ◽  
Α Phase ◽  
High Energy Ball Mill ◽  
Powder Particles ◽  
Energy Ball

A novel biocomposite Ti-35wt%Nb-2.5wt%Sn-15wt%HA powders was synthesized by high energy ball mill(HEBM) for various periods of time. The microstructure and characteristics of the milled powder particles were investigated. Results showed that in the composite powders milled for 4h, Ti was still exhibited primary α phase, with the increase of ball milling time up to 8h, Ti transformed into primary β phase and a little α phase, after ball milling for 12h, Ti transformed into β phase fully. the transform temperature was 380.06°C. And TEM and PSD results indicated that nanostructure was obtained after 12h milling..

Preparation of Cu-Zn Alloy by Different High Energy Ball Milling

2011 ◽  
Vol 412 ◽  
pp. 259-262
Author(s):  
Kai Jun Wang ◽  
Xiao Lan Cai ◽  
Hua Wang ◽  
Jin Hu ◽  
Yun Feng Zhang
Keyword(s):  
Ball Milling ◽  
Milling Time ◽  
High Energy ◽  
High Energy Ball Milling ◽  
Attrition Mill ◽  
Phase Form ◽  
Elemental Copper ◽  
Energy Ball ◽  
New Phase ◽  
Zn Alloy

Cu-Zn alloy was prepared by high energy ball milling of elemental copper and zinc by the Simoloyer attrition mill, the different parameters such as milling time, ball-to-powder ratio and rotational speeds were analyzed. The results show that the different Cu-Zn alloy phase can be produced by different ball milling parameters, It has been found that milling time is highly significant to refining process, and the ratios of ball to powder are also benefited to the new phase form.

Development of Ni/h-BN Self-Lubricating Composite Powder by High-Energy Ball Milling

2016 ◽  
Vol 869 ◽  
pp. 277-282
Author(s):  
Moisés Luiz Parucker ◽  
César Edil da Costa ◽  
Viviane Lilian Soethe
Keyword(s):  
Ball Milling ◽  
Milling Time ◽  
Solid Lubricants ◽  
High Energy ◽  
High Energy Ball Milling ◽  
Second Phase ◽  
Average Particle ◽  
Composite Powders ◽  
The Matrix ◽  
Energy Ball

Solid lubricants have had good acceptance when used in problem areas where the conventional lubricants cannot be applied: under extreme temperatures, high charges and in chemically reactive environments. In case of materials manufactured by powder metallurgy, particles of solid lubricants powders can be easily incorporated to the matrix volume at the mixing stage. In operation, this kind of material provides a thin layer of lubricant that prevents direct contact between the surfaces. The present study aimed at incorporating particles of second phase lubricant (h-BN) into a matrix of nickel by high-energy ball milling in order to obtain a self-lubricating composite with homogeneous phase distribution of lubricant in the matrix. Mixtures with 10 vol.% of h-BN varying the milling time of 5, 10, 15 and 20 hours and their relationship ball/powder of 20:1 were performed. The effect of milling time on the morphology and microstructure of the powders was studied by X-ray diffraction, SEM and EDS. The composite powders showed reduction in average particle size with increasing milling time and the milling higher than 5 hours resulted in equiaxial particles and the formation of nickel boride.

Ball milling for the formation of nanocrystalline intermetallic compounds from Ni-Ti elemental powders

2018 ◽  
Vol 27 (5-6) ◽  
Author(s):  
Pardeep Sharma
Keyword(s):  
Intermetallic Compounds ◽  
Milling Time ◽  
Lattice Strain ◽  
Research Work ◽  
High Energy ◽  
Mechanically Alloyed ◽  
Nano Crystalline ◽  
High Energy Ball Mill ◽  
Productive Process ◽  
Energy Ball

AbstractIn the present research work nickel (Ni) and titanium (Ti) elemental powder with an ostensible composition of 50% of each by weight were mechanically alloyed in a planetary high energy ball mill in diverse milling circumstances (10, 20, 30 and 60 h). The inspection exposed that increasing milling time leads to a reduction in crystallite size, and after 60 h of milling, the Ti dissolved in the Ni lattice and the NiTi (B2) phase was obtained. The lattice strain of ball milled mixtures augmented from 0.15 to 0.45 at 60 h milling. With increase in milling time the morphology of pre-alloyed powder changed from lamella to globular. Annealing of as-milled powders at 1100 K for 800 s led to the formation of NiTi (B19′), grain growth and the release of internal strain. The result indicated that this technique is a powerful and highly productive process for preparing NiTi intermetallic compounds with a nano-crystalline structure and appropriate morphology.

Carbon Nanotubes Reinforced Aluminum Matrix Composites by High-Energy Ball Milling

2010 ◽  
Vol 150-151 ◽  
pp. 1163-1166 ◽  
Author(s):  
Xiao Fei Wang ◽  
Xiao Lan Cai
Keyword(s):  
Mechanical Properties ◽  
Ball Milling ◽  
Milling Time ◽  
Aluminum Matrix ◽  
High Energy ◽  
High Energy Ball Milling ◽  
Aluminum Matrix Composites ◽  
Matrix Composites ◽  
Energy Ball ◽  
Rotary Speed

CNT-reinforced aluminum matrix composites was produced by high-energy ball milling, the effect of rotary speed and milling time on the particle size distribution,the density and hardness of CNT-aluminum matrix composites were studied,it was observed that the rotary speed and milling time have an important effect on the mechanical properties of the CNT-aluminum matrix composites.

Improved lithium insertion/extraction properties of single-walled carbon nanotubes by high-energy ball milling

2008 ◽  
Vol 23 (9) ◽  
pp. 2458-2466 ◽  
Author(s):  
JiYong Eom ◽  
HyukSang Kwon
Keyword(s):  
Ball Milling ◽  
Milling Time ◽  
Single Walled Carbon Nanotubes ◽  
High Energy ◽  
Milling Process ◽  
Extraction Properties ◽  
Energy Ball ◽  
Insertion Sites ◽  
Walled Carbon Nanotubes ◽  
Ball Milling Time

The effects of ball milling on lithium (Li) insertion/extraction properties into/from single-walled carbon nanotubes (SWNTs) were investigated. The SWNTs were synthesized on supported catalysts by thermal chemical-vapor deposition method, purified, and mechanically ball-milled by high-energy ball milling. The purified SWNTs and the ball-milled SWNTs were electrochemically inserted/extracted with Li. The structural and chemical modifications in the ball-milled SWNTs change the insertion/extraction properties of Li ions into/from the ball-milled SWNTs. The reversible capacity (Crev) increases with increase in the ball milling time, from 616 mAh/g (Li1.7C6) for the purified SWNTs to 988 mAh/g (Li2.7C6) for the ball-milled SWNTs. The undesirable irreversible capacity (Cirr) decreases continuously with increase in the ball milling time, from 1573 mAh/g (Li4.2C6) for the purified SWNTs to 845 mAh/g (Li2.3C6) for the ball-milled SWNTs. The enhancedCrevof the ball-milled SWNTs is presumably due to a continuous decrease in theCirrbecause the SWNTs develop a densely packed structure on the ball milling process. The insertion of Li ions into the ball-milled SWNTs is facilitated by various Li insertion sites formed during the ball milling process in spite of small surface area than the purified SWNTs. Lithium ions inserted into various insertion sites enhance theCrevin the ball-milled SWNTs with the large voltage hysteresis by hindrance of the extraction of Li ions from the ball-milled SWNTs. In addition, the ball-milled samples exhibit more stable cycle capacities than the purified samples during the charge/discharge cycling.

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