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Japan s largest platform for academic e-journals J-STAGE is a full text database for reviewed academic papers published by Japanese societies
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(PDF) Ultralow-Temperature Superplasticity in Nanoceramic
NANO LETTERS Ultralow-Temperature Superplasticity in 2005 Vol. 5 No. 12 Nanoceramic Composites Guo-Dong Zhan Department of Chemical and Biological Engineering the UniVersity of Colorado at Boulder Colorado 80309 Javier E. Garay Department of Mechanical Engineering the UniVersity of California RiVerside California 92521 Amiya K. Mukherjee Department of Chemical
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THE EFFECT OF NANO-TITANIA ADDITION ON THE
Figure 1 shows the effect of nano-titania content on SFV of the high-alumina low-cement refractory castable as a function of time. The results indicate that with increase of nano-titania particles in castable composition SFV tends to decrease. The nano-titania particles have high surface area that leads to
Get PriceDensification and Grain Growth of Fe‐Doped and Fe/Y
The effect of iron and iron/yttrium codoping on the densification and grain growth of ultra high‐purity (99.995 ) fine‐grained alumina has been studied. The experiments were carried out under both o
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Effect of Micro-Nano Particle Size Admixture on the
Rapid grain growth occurs at the final-stage of the sintering process 14 . it was found that densification of all compositions was inferior except 100 nano alumina. To improve the densification behavior sintering time was increased to 8 hours with the pre-sintering time of 12 hrs. By mixing 5 and 10 nano-alumina the abnormal grain
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On the densification mechanism of nano grained Yttrium
The sintering densification mechanism of nano grained Yttrium aluminum garnet transparent ceramic during high pressure sintering process can be divided into three period. The first sintering stage can be described as plastic deformation after yield point. The intermediate stage is conducted by grain boundary viscous sliding.
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On the densification mechanism of nano grained Yttrium
Jan 01 2018 · The sintering densification mechanism of nano grained Yttrium aluminum garnet transparent ceramic during high pressure sintering process can be divided into three period. The first sintering stage can be described as plastic deformation after yield point. The intermediate stage is conducted by grain boundary viscous sliding.
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THE EFFECT OF NANO-TITANIA ADDITION ON THE
Figure 1 shows the effect of nano-titania content on SFV of the high-alumina low-cement refractory castable as a function of time. The results indicate that with increase of nano-titania particles in castable composition SFV tends to decrease. The nano-titania particles have high surface area that leads to
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Densification of Ca-Doped Alumina Nanopowders Prepared
Ca-doped alumina nanopowders suitable for low-temperature finer-grained densification were 0.10 mol Ca-doping 5 mass α-alumina seeding and a calcination temperature of 900˚C. These conditions led to the formation of new nano-sized alumina powders which consisted of 80 nm α-alumina particles and γ-alumina nanoparticles.
Get PriceDensification mechanism of the ultra-fast sintering dense
The results show that a high heating rate can delay the frozen point of densification by the overlapping of surface/grain boundary diffusion and lattice diffusion resulting in the extension of grain size distribution thus providing a high relative density due to improved grain rearrangement. The high sintering temperature and high
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Rapid densification of alumina ceramics with fine grains
Request PDF Rapid densification of alumina ceramics with fine grains and high strength A submicron α-alumina powder without any additives was sintered to 98.5 of its theoretical density at
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Stress-enhanced grain growth during high pressure spark
The SPS process enables rapid densification of ceramic powder at relatively lower temperatures which Commercial alumina nano-powder with an initial particle size of about 75 nm was used in this study. SPS parameters for fine-grained alumina (grain size at
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(PDF) Sintering of a nano-crystalline metastable alumina
As a matter of fact the during the thermal treatment such as a-alumina final stage of sintering must be performed at very high yttria ZnO and a-alumina-based composites 15 18 . temperatures to achieve full densification but inducing On the contrary if reference is made to transition a relevant grain
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Advanced ceramicsDensification Britannica
Advanced ceramicsAdvanced ceramicsDensification Like traditional ceramics advanced ceramics are densified from powders by applying heat—a process known as sintering. Unlike traditional ceramics however advanced powders are not bonded by the particle-dissolving action of glassy liquids that appear at high temperatures. Instead solid-state sintering predominates.
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Fast densification of nanocrystalline yttria ceramics
Mar 25 2015 · Dense nanocrystalline yttria ceramics without grain growth were obtained within a short densification period by a method combining SHS reaction and quick pressing (SHS-QP). The reactive mixtures consisting of Ni and Al with TiC as a diluent were used as a heat source. An yttria compact was inserted inside the reactants and warmed up by reaction heat at a heating rate of above
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Nanocrystalline materialWikipedia
A nanocrystalline (NC) material is a polycrystalline material with a crystallite size of only a few nanometers.These materials fill the gap between amorphous materials without any long range order and conventional coarse-grained materials. Definitions vary but nanocrystalline material is commonly defined as a crystallite (grain) size below 100 nm. Grain sizes from 100–500 nm are typically
Get PriceInfluence of yttria additions on the densification of nano
Aug 10 2016 · The high hardness for all specimens was recorded at a sintering temperature of 1650 °C and attributed to the formation of YAG and grain growth of alumina. Furthermore the addition of yttria and sintering temperature showed a significant effect on the sintered specimens microstructure densification process and phase composition.
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Fast densification of nanocrystalline yttria ceramics
Mar 25 2015 · Dense nanocrystalline yttria ceramics without grain growth were obtained within a short densification period by a method combining SHS reaction and quick pressing (SHS-QP). The reactive mixtures consisting of Ni and Al with TiC as a diluent were used as a heat source. An yttria compact was inserted inside the reactants and warmed up by reaction heat at a heating rate of above
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THE EFFECT OF NANO-TITANIA ADDITION ON THE
Figure 1 shows the effect of nano-titania content on SFV of the high-alumina low-cement refractory castable as a function of time. The results indicate that with increase of nano-titania particles in castable composition SFV tends to decrease. The nano-titania particles have high surface area that leads to
Get PriceFabrication of Ultrafine-Grained Alumina Ceramics by Two
Rapid Densification of Nano‐Grained Alumina by High Temperature and Pressure with a Very High Heating Rate. Article. Mar 2007 (due to the small grain size) high density and density
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Densification of Nanostructured Alumina Assisted by Rapid
The drastic reduction in sintering temperature from 1600 C to 1300 C is possible by rapid nucleation of the stable Α-alumina phase. It is achieved by introducing the compacted pellet of bayrite fine particles derived by the sol-gel process in a furnace at 1250 C the temperature high enough for the rapid transformation to Α-alumina.
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"Effect of nano clay and nano zirconia addition on the
The properties of alumina largely depend on its densification. Generally sintering is associated with densification by mass transport phenomenon grain growth at high temperature. To achieve better densification a lot of research has been conducted on finding the sintering additives and its effect on properties of alumina. Studies have shown
Get PriceMicrostructural evolution and mechanism of grain growth in
Meng F C Fu Z Y Zhang J Y et al. Rapid densification of nano-grained alumina by high temperature and pressure with a very high heating rate. J Am Ceram Soc
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Effects of heating rate on alumina grain growth SpringerLink
Jan 31 2015 · A rapid-heating method in the absence of electric/magnetic field was achieved by introducing a self-propagating-combustion (SHS) as heating source. The effect of heating rate on the alumina grain growth was explored based on this rapid-heating method. Comparing with the alumina prepared by two different heating ratios (greater than 1 000 °C/min in SHS and about 50 °C/min in
Get Price(PDF) Effect of nano-grain size on the ionic conductivity
The noticeable increase in ionic sintered at 1050 C 1150 C and 1200 C. conductivity in the nano range can be attributed to the change in grain-boundary characteristics from barrier to the i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 7 ( 2 0 1 2 ) 5 1 1 e5 1 7 517 conducting channels associated with ultra fine grain
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