Novel Fabrication Method of FGM Containing Nano-Particles - Centrifugal Mixed-Powder Method -

2010 ◽  
Vol 434-435 ◽  
pp. 751-756
Author(s):  
Yoshimi Watanabe ◽  
Hisashi Sato
Keyword(s):  
Centrifugal Force ◽  
Powder Mixture ◽  
Matrix Material ◽  
Nano Particles ◽  
Nano Particle ◽  
Fabrication Method ◽  
Mixed Powder ◽  
Centrifugal Method ◽  
Powder Method ◽  
The Difference

One of the fabrication methods for functionally graded materials (FGMs) is a centrifugal method, which is an application of the centrifugal casting technique. In the method, a centrifugal force applied to a homogeneous molten composite assists the formation of the desired gradation. The compositional gradient is then achieved primarily by the difference in the centrifugal force produced by the difference in density between the molten metal and solid particles. The centrifugal method has the advantage that it is possible to fabricate large size products with low cost. However, disadvantage of the centrifugal method is the difficult for the gradual distribution of small particles. In this study, we proposed a novel fabrication method, centrifugal mixed-powder method, by which we can obtain FGMs containing nano-particle. On first of this processing, powder mixture of functional nano-particle and matrix material is inserted into rotating mold. After that, matrix ingot is melted in crucible and then the melt is poured into the rotating mold with powder mixture. At that time, powder of matrix material is melted by matrix melt poured from crucible. Finally, an FGM ring with functional nano-particles distributed on its surface is obtained. Using this processing method, Al-based FGMs containing TiO2 nano-particles or SiC particles on its surface were fabricated.

Fabrication of Al-Based FGM Containing TiO2 Nano-Particles by a Centrifugal Mixed-Powder Method

2009 ◽  
Vol 631-632 ◽  
pp. 441-447 ◽  
Author(s):  
Yoshifumi Inaguma ◽  
Hisashi Sato ◽  
Yoshimi Watanabe
Keyword(s):  
Powder Mixture ◽  
Matrix Material ◽  
Functional Materials ◽  
Processing Method ◽  
Functionally Graded ◽  
Nano Particles ◽  
Nano Particle ◽  
Mixed Powder ◽  
Centrifugal Method ◽  
Powder Method

Centrifugal method is often applied as the fabrication process of Functionally Graded Materials (FGMs). This is because that this processing method can fabricate FGMs with large size, easily. However, this processing method has a serious problem, namely it is difficult to disperse particles with small size and low wet ability with matrix. Many of powders with nano or very fine particle size often have attractive attention as functional materials. Therefore the above problem of the centrifugal method should be improved. In this study, we proposed a centrifugal mixed-powder method as novel processing technique for the fabrication of FGM containing nano-particle. On first of this processing, powder mixture of functional nano-particle and matrix material is inserted into rotating mold. After that, matrix ingot is melted in crucible and then the molten matrix is poured into the rotating mold with powder mixture, and then, powder of matrix material will be melted by the heat from molten matrix poured from crucible. Finally, an FGM ring with functional nano-particles distributed on its surface can be obtained. Using this processing method, Al-based FGM containing TiO2 nano-particles on its surface could be fabricated. TiO2 particle has approximately 500nm in diameter. From microstructural observation, it was found that TiO2 particles were successfully distributed on surface of FGM ring. Also, hardness on the surface of the FGM ring was higher than that on inner part due to the dispersion hardening.

scholarly journals A Novel Fabrication Method for Functionally Graded Materials under Centrifugal Force: The Centrifugal Mixed-Powder Method

Materials ◽  
2009 ◽  
Vol 2 (4) ◽  
pp. 2510-2525 ◽  
Author(s):  
Yoshimi Watanabe ◽  
Yoshifumi Inaguma ◽  
Hisashi Sato ◽  
Eri Miura-Fujiwara
Keyword(s):  
Centrifugal Force ◽  
Functionally Graded Materials ◽  
Functionally Graded ◽  
Fabrication Method ◽  
Mixed Powder ◽  
Graded Materials ◽  
Powder Method

Joining of AlN and Al with Compositional Graded Layer by Centrifugal Mixed-Powder Method

2018 ◽  
Vol 941 ◽  
pp. 1978-1983 ◽  
Author(s):  
Yoshimi Watanabe ◽  
Masaki Murase ◽  
Hisashi Sato ◽  
Hideaki Tsukamoto
Keyword(s):  
Thermal Stress ◽  
Stress Relaxation ◽  
Centrifugal Force ◽  
Mixed Powder ◽  
Powder Method ◽  
Thermal Stress Relaxation

In this study, joining of AlN and Al with compositional graded layer is made by centrifugal mixed-powder method (CMPM). The mixed-powder of AlN particles and Al particles is inserted into a spinning mold with bulk-shaped AlN, and then molten Al is poured into the spinning mold with the mixed-powder and bulk-shaped AlN. As a result, the molten Al penetrates into the space between the mixed-powder by the centrifugal force, and at the same time, the Al particles can be melted by heat from the molten Al. Then AlN and Al can be joined with compositional graded layer after solidification. Micromechanics-based analysis is also employed to understand the thermal stress relaxation by the compositional graded layer.

Fabrication of Metal-Based Functionally Graded Grinding Wheel by a Centrifugal Mixed-Powder Method

2012 ◽  
Vol 706-709 ◽  
pp. 661-666 ◽  
Author(s):  
Eri Miura-Fujiwara ◽  
Hisashi Sato ◽  
Motoko Yamada ◽  
Yoshimi Watanabe
Keyword(s):  
Centrifugal Force ◽  
Alloy System ◽  
Functionally Graded ◽  
Grinding Wheel ◽  
Migration Behavior ◽  
Mixed Powder ◽  
Cross Sectional ◽  
Diamond Grinding Wheel ◽  
Powder Method ◽  
Diamond Grinding

Metal-bonded diamond grinding wheel was fabricated by a centrifugal mixed-powder method. The centrifugal mixed-powder method is a novel and effective casting process to obtain functionally graded material (FGM). At the beginning, we performed fundamental experiments using Al-Si alloy system for the purpose of knowing the migration behavior of mixed-powder under centrifugal force. Al-Si hypereutectic alloyed-powder or mixed-powder of Al and Si particles was placed into the mold, and then Al molten metal was cast under a centrifugal force. Cross sectional microstructure observation and quantitative analysis of Si content were conducted using an electron probe microanalyzer. Amount of Si decreased with receding from a mixed-powder region. Si concentration gradient in the sample fabricated Al-Si powder was smaller than the one fabricated using mixed-powder of Al and Si particles. Subsequently, φ 20 mm Cu/diamond grinding wheel was fabricated by the casting method. Graded diamond distribution was successfully obtained.

518 Fabrication of Metal-Based Functionally Graded Material Dispersing Nano-Particles by a Centrifugal Mixed-Powder Method

2009 ◽  
Vol 2009.17 (0) ◽  
pp. _518-1_-_518-2_
Author(s):  
Hisashi Sato ◽  
Yoshifumi Inaguma ◽  
Motoko Yamada ◽  
Tetsuya Azuma ◽  
Eri Miura-Fujiwara ◽  
...  
Keyword(s):  
Functionally Graded Material ◽  
Functionally Graded ◽  
Nano Particles ◽  
Mixed Powder ◽  
Powder Method ◽  
Graded Material

Asymmetric Carbon Nanotube Dimers for Novel Sensing Applications

2021 ◽  
Vol 35 (11) ◽  
pp. 1320-1321
Author(s):  
Sumitra Dey ◽  
Ahmed Hassan
Keyword(s):  
Carbon Nanotube ◽  
Field Distribution ◽  
Electromagnetic Coupling ◽  
Nano Particles ◽  
Computational Experiments ◽  
Nano Particle ◽  
Relative Location ◽  
Sensing Applications ◽  
The Difference ◽  
Asymmetric Carbon

In this work, we study the use of asymmetric carbon nanotube (CNT) dimers for the contactless detection of foreign nano-particles. Asymmetric CNT dimers create a unique field distribution, through the electromagnetic coupling, which in turn generates two distinct resonances representing the bonding and anti-bonding modes. The presence of a foreign nano-particle (NP) in the vicinity of the CNT dimer perturbs the dimer’s field distribution and causes the bonding and anti-bonding resonances to shift by unequal amounts depending on the NP location. By studying the difference in the shift of the bonding and the anti-bonding resonances, we show that the NP relative location can be reconstructed. The computational experiments performed in this work show how asymmetric CNT dimers can be used for novel sensing applications.

Fabrication of Cu-Based Functionally Graded Materials Dispersing Fine Sic Particles by a Centrifugal Mixed-Powder Method

2010 ◽  
Vol 638-642 ◽  
pp. 2160-2165 ◽  
Author(s):  
Hisashi Sato ◽  
Yoshifumi Inaguma ◽  
Yoshimi Watanabe
Keyword(s):  
Solid Particle ◽  
Powder Mixture ◽  
Volume Fraction ◽  
Processing Technique ◽  
Functionally Graded ◽  
Solid Particles ◽  
Mixed Powder ◽  
Powder Method ◽  
Sic Particles ◽  
Graded Material

Recently, a centrifugal mixed-powder method has been proposed as the processing technique of functionally graded material (FGM) containing fine solid-particles. In this study, Cu-based FGM containing SiC particles was fabricated using this technique. Although the density of SiC is smaller than that of Cu, these SiC particles are successfully distributed on surface of the cylindrical FGM. From this result, it is clear the movement of solid particle in powder mixture during casting is small. Therefore, the gradual distribution of the solid particle can be formed by the control of the volume fraction of solid-particles in powder mixture. Also, it is found that smaller SiC particle can improve the hardness on the surface of the FGMs effectively rather than larger one. In this study, the assignment of the centrifugal mixed-powder method was suggested from the obtained results.

Numerical Simulation for Microconvection Around Nano-Particle With Brownian Motion in Liquid

2003 ◽  
Author(s):  
B. X. Wang ◽  
H. Li ◽  
X. F. Peng ◽  
L. X. Yang
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Brownian Motion ◽  
Numerical Model ◽  
Temperature Gradient ◽  
Transfer Process ◽  
Heat Transfer Process ◽  
Nano Particles ◽  
Analytic Method ◽  
Nano Particle

The development of a numerical model for analyzing the effect of the nano-particles’ Brownian motion on the heat transfer is described. By using the Maxwell velocity distribution relations to calculate the most possible velocity of fluid molecules at certain temperature gradient location around the nano-particle, the interaction between fluid molecules and one single nano-particle is analyzed and calculated. Based on this, a syntonic system is proposed and the coupled effect that Brownian motion of nano-particles has on fluid molecules is simulated. This is used to formulate a reasonable analytic method, facilitating laboratory study. The results provide the essential features of the heat transfer process, contributed by micro-convection to be considered.

scholarly journals Modification and Improvement of Fe3O4-Embedded Poly(thiophene) Core/Shell Nanoparticles for Cadmium Removal by Cloud Point Extraction

2020 ◽  
Vol 1 (1) ◽  
pp. 20-27
Keyword(s):  
Aqueous Solution ◽  
Cloud Point ◽  
Cloud Point Extraction ◽  
Calibration Graph ◽  
Nano Particles ◽  
Extraction Time ◽  
Ionic Surfactant ◽  
Nano Particle ◽  
Cadmium Removal ◽  
Shell Nanoparticles

Cloud Point Extraction (CPE) as an effective method for pre-concentration and separation of cadmium from aqueous solution is widely utilized. This study involves a surfactant mediated CPE procedure in order to remove cadmium from waste water using Polythiophene nanoparticle and Triton X- 100 as a non – ionic surfactant. Polythiophene – coated iron nanoparticles was successfully synthesized with novel method and as a super magnetic nano-particles (MNPs) for cadmium removal from aqueous solution was evaluated. Polythophene nano-particles emulsifying method have been synthesized and fabricated. Fabricated nano-particle was characterized by Fourier-transform infrared spectroscopy (FTIR), and analysed transmission electron microscopy (SEM). Effects of pH, buffer volume, extraction time, temperature, amount of nano-particle were essentially investigated. To reach in optimum conditions, related experiments were replicated and accomplished as well. For removal of cadmium by CPE approach the optimization conditions were gained at pH = 7 , volume of buffer acid 1.5 millilitre , electrolyte concentration (NaCl) of 10 -3 mole L-1 , Trinton concentration 5 %, cloud point temperature 80 0 C , extraction time 40 minutes, and 5 mg of modified polythiophene nano-particle. The calibration graph was liner with a correlation coefficient of 0. 9984 and represents appropriate liner correlation with an amount and concentration. The results revealed that 5 gram of modified nanoparticle can significantly increase the efficiency of cadmium removal.

3D Measurements of Nano-Particle Transport in Complex 2.5D Micro-Models

2015 ◽  
Author(s):  
Jagannath Upadhyay ◽  
Daniel S. Park ◽  
Karsten E. Thompson ◽  
Dimitris E. Nikitopoulos
Keyword(s):  
Particle Velocity ◽  
Particle Transport ◽  
Three Dimensional ◽  
Laser Scanning Microscopy ◽  
Nano Particles ◽  
Confocal Laser ◽  
Nano Particle ◽  
Micro Model ◽  
Micro Particle Image Velocimetry

A confocal Micro-Particle Image Velocimetry (C-μPIV) technique along with associated post image processing algorithms is established to quantify three dimensional distributions of nano-particle velocity and concentration at the micro-scale (pore-scale) in 2.5D porous media designed from a Boise rock sample. In addition, an in-situ, non-destructive method for measuring the geometry of the micro-model, including its depth, is described and demonstrated. The particle experiments use 900 nm fluorescence labeled polystyrene particles at a flow rate of 10 nLmin−1 and confocal laser scanning microscopy (CLSM), while in-situ geometry measurements use regular microscope along with Rhodamine dye and a depth-to-fluorescence-intensity calibration. Image post-processing techniques include elimination of background noise and signal from adsorbed nano-particle on the inner surfaces of the micro-model. In addition, a minimization of depth of focus technique demonstrates a capability of optically thin slice allowing us to measure depth wise velocity in 2.5D micro-model. The mean planar components of the particle velocity of the steady-state flow and particle concentration distributions were measured in three dimensions. Particle velocities range from 0.01 to 122 μm s−1 and concentrations from 2.18 × 103 to 1.79 × 104 particles mm−2. Depth-wise results show that mean velocity closer to the top wall is comparatively higher than bottom walls, because of higher planar porosity and smooth pathway for the nano-particles closer to the top wall. The three dimensional micro-model geometry reconstructed from the fluorescence data can be used to conduct numerical simulations of the flow in the as-tested micro-model for future comparisons to experimental results after incorporating particle transport and particle-wall interaction models.

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