Preparation Process of Metal Matrix Micro/Nano-Powders Reinforced by Nanometer Particles

2009 ◽  
Vol 60-61 ◽  
pp. 155-159 ◽  
Author(s):  
Hong Yu Wang ◽  
Dun Wen Zuo ◽  
Shou Xin Yu ◽  
Dan Zhang
Keyword(s):  
Ball Milling ◽  
Metal Matrix ◽  
Milling Time ◽  
High Energy ◽  
Preparation Process ◽  
Composite Powders ◽  
Additive Process ◽  
Additive Content ◽  
Nanometer Particles ◽  
Ball Milling Time

The compound of micron powders and nanometer powders is a magnificent step in the application and development of metal matrix composite reinforced by nanometer particles. By taking nano-Al2O3 powders and Ni-based micron powders as the research object, the preparation process of metal matrix micro/nano-powders reinforced by nanometer particles with high energy ball-milling is discussed from three aspects: the additive process of nanometer powders, the additive content of nanometer powders, and the required ball-milling time in the paper. The results show that the additive process of nanometer powders which uses directly the dispersed uniformly nanometer suspensions as grinding medium can effectively decrease and avoid nanometer powders’ agglomeration of composite powders. Nanometer particles are well distributed in the composite powders. The optimum additive content of nanometer powders is consistent with the theoretical model of mixture ratio, which is determined by the ratio of the average diameter of micron powders and nanometer powders and their density of corresponding solid materials. Meanwhile, the required ball-milling time for preparation of better uniformity composite powders is no more than 0.5hr. This implies that the preparation process has a high productivity. Moreover, the preparation process is verified through other nanometer powders including nano-SiC powders and nano-CeO2 powders.

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.

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.

Fabrication of Carbon Nanotube/Aluminum Matrix Composites by Ball Milling and Cold Press Processing

2021 ◽  
Vol 878 ◽  
pp. 89-97
Author(s):  
Shogo Kimura ◽  
Junki Ueda ◽  
Hideaki Tsukamoto
Keyword(s):  
Carbon Nanotube ◽  
Ball Milling ◽  
Metal Matrix ◽  
Milling Time ◽  
Aluminum Matrix ◽  
High Strength ◽  
Aluminum Matrix Composites ◽  
Matrix Composites ◽  
Ball Milling Time ◽  
Al Matrix

Carbon nanotube (CNT) has been one of promising candidates as a reinforcement in metal matrix composites (MMCs) for its variety of excellent properties such as lightweight, high strength etc. It is necessary to disperse CNT to the level of each one in order to lead to efficiently reflect the excellent essential physical properties of CNT in the composites. This research investigates fabrication processes linked with dry ball milling and cold pressing followed by sintering to uniformly disperse CNT in aluminum (Al) matrix. It was found that dispersibility of CNT were improved with increasing ball milling time based on observation of morphology of mixed powders and the composites using SEM. Vickers hardness and tensile strength of CNT/ Al composites increased with increasing ball milling time up to 24 hours, while they were constant or decreased because of increase of voids in case of longer than 24 hours of ball milling time.

Al/Al2O3 Nanocomposite Produced by ECAP

2013 ◽  
Vol 762 ◽  
pp. 457-464 ◽  
Author(s):  
Riccardo Casati ◽  
Matteo Amadio ◽  
Carlo Alberto Biffi ◽  
David Dellasega ◽  
Ausonio Tuissi ◽  
...  
Keyword(s):  
Ball Milling ◽  
Metal Matrix ◽  
Numerical Models ◽  
High Energy ◽  
Sem Analysis ◽  
High Energy Ball Milling ◽  
Composite Powders ◽  
Metal Matrix Nanocomposites ◽  
Angular Pressing ◽  
Energy Ball

Metal matrix nanocomposites have been produced by powder metallurgy route. Al and nanoAl2O3powders were grinded through high energy ball milling. Then, the composite powders were sintered by Equal Channel Angular Pressing (ECAP). 12 ECAP passes were carried out in order to improve the dispersion of the hard particles. SEM analysis was performed to investigate the distribution of the ceramic nanoparticles within the matrix. Hardness tests were executed to evaluate the mechanical behavior of the nanocomposites. Finally, mechanical strength values obtained by numerical models were compared with those estimated from hardness measurements. High energy ball milling followed by ECAP process revealed to be a suitable route for the production of metal matrix composites reinforced with well dispersed nanoparticles.

Spark Plasma Sintering of High-Energy Ball-Milled ZrB2 and HfB2 Powders with 20vol% SiC

2018 ◽  
Vol 941 ◽  
pp. 1990-1995
Author(s):  
Naidu V. Seetala ◽  
Cyerra L. Prevo ◽  
Lawrence E. Matson ◽  
Thomas S. Key ◽  
Ilseok I. Park
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Ball Milling ◽  
Milling Time ◽  
High Energy ◽  
Micro Hardness ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Energy Ball ◽  
Ball Milling Time

ZrB2 and HfB2 with incorporation of SiC are being considered as structural materials for elevated temperature applications. We used high energy ball milling of micron-size powders to increase lattice distortion enhanced inter-diffusion to get uniform distribution of SiC and reduce grain growth during Spark Plasma Sintering (SPS). High-energy planetary ball milling was performed on ZrB2 or HfB2 with 20vol% SiC powders for 24 and 48 hrs. The particle size distribution and crystal micro-strain were examined using Dynamic Light Scattering Technique and x-ray diffraction (XRD), respectively. XRD spectra were analyzed using Williamson-Hall plots to estimate the crystal micro-strain. The particle size decreased, and the crystal micro-strain increased with the increasing ball milling time. The SPS consolidation was performed at 32 MPa and 2,000°C. The SEM observation showed a tremendous decrease in SiC segregation and a reduction in grain size due to high energy ball milling of the precursor powders. Flexural strength of the SPS consolidated composites were studied using Four-Point Bend Beam test, and the micro-hardness was measured using Vickers micro-indenter with 1,000 gf load. Good correlation is observed in SPS consolidated ZrB2+SiC with increased micro-strain as the ball milling time increased: grain size decreased (from 9.7 to 3.2 μm), flexural strength (from 54 to 426 MPa) and micro-hardness (from 1528 to 1952 VHN) increased. The correlation is less evident in HfB2+SiC composites, especially in micro-hardness which showed a decrease with increasing ball milling time.

Nanocrystalline Cu90Nb10 Alloy Produced by Mechanical Alloying

2013 ◽  
Vol 750-752 ◽  
pp. 752-755
Author(s):  
C.J. Li ◽  
Q.X. Zhang ◽  
Q. Yuan ◽  
J. Tan ◽  
L. Teng ◽  
...  
Keyword(s):  
Mechanical Alloying ◽  
Ball Milling ◽  
Milling Time ◽  
High Energy ◽  
Deformation Degree ◽  
Solid Solution Strengthening ◽  
Fine Grain ◽  
Powder Particles ◽  
Energy Ball ◽  
Ball Milling Time

Nanocrystalline Cu90Nb10 alloy was produced by high energy ball milling mechanical alloying (MA). The effects of ball milling time on the microstructure and mechanical property of this alloy in the process of MA were investigated. The results show: up to 10 at.% Nb could be dissolved into Cu matrix by MA; the powder particles became compacted and homogeneous with increasing the ball milling time, and the deformation degree also increased synchronously; the grain size of this alloy was refined gradually, and it reached the minimum value of 11.5 nm after 30h milling; the microhardness of this alloy increased with increasing the milling time, and it obtained the maximum value of 328 Hv after 30h milling. The obvious reinforcement of this alloy may be due to the comprehensive effects of the fine grain strengthening, the solid solution strengthening and the strain strengthening.

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