Using the development tool C++ Builder and adopting object oriented programming method, the ceramic/metal gradient thermal barrier coating design software (CCDS) is developed according to software engineering criterio...
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Using the development tool C++ Builder and adopting object oriented programming method, the ceramic/metal gradient thermal barrier coating design software (CCDS) is developed according to software engineering criterion. The CCDS, which has user-friendly interface, is composed of three functional modules: preprocess module, analysis module and post process module. In addition, this software is attached with an optimal design module and an expert module. The calculation and design of the ceramic/metal gradient thermal barrier coating can be carried out by the CCDS, and the numerical results show good agreement with the analytical results.
e effect of sintering temperature on the microstructure, nonlinear electrical behavior, and dielectric properties of the Y2O3-doped WO3 ceramics was studied. The decrease in breakdown voltage directly relates to the g...
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e effect of sintering temperature on the microstructure, nonlinear electrical behavior, and dielectric properties of the Y2O3-doped WO3 ceramics was studied. The decrease in breakdown voltage directly relates to the grain growth of WO3 grains when increasing the sintering temperatures from 1050 to 1200 'C. The capacitor-varistor of WO3- 0.8 mol％ Y2O3 composite sintered at 1150 °C exhibits the maximal nonlinear coefficient of 3.5 and the highest dielectric constant of 1.13 x 104. However, higher sintering temperature than 1150 °C is not favorable for the nonlinear electrical behavior of the WO3 ceramics. The best nonlinear properties of the samples sintered at 1150 'C can be explained by the most efficient boundary barrier layer with can be formed sintered at the proper temperature.
Potassium lithium niobate (KLN:K3Li2Nb5O15) thin films have been deposited on quartz glass by pulsed laser deposition (PLD) technique using a stoichiometric KLN target, which was prepared by solid reaction with K2CO3,...
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Potassium lithium niobate (KLN:K3Li2Nb5O15) thin films have been deposited on quartz glass by pulsed laser deposition (PLD) technique using a stoichiometric KLN target, which was prepared by solid reaction with K2CO3, Li2CO3, and Nb2O5 powders as starting materials. X-ray diffraction (XRD) and Raman studies have revealed that tetragonal tungsten-bronze-type structure of KLN films with (310) preferred orientation could be achieved at the substrate temperature of 700°C and the oxygen partial pressure of 10 Pa. The average transmittance of as-deposited thin films in the visible range was nearly 90%.
The temperature field of two types of porous graded ZrO2 subjected to thermal shock loading is analyzed in this paper using the finite‐element method. The numerical simulation results indicate that the structure of Z...
The temperature field of two types of porous graded ZrO2 subjected to thermal shock loading is analyzed in this paper using the finite‐element method. The numerical simulation results indicate that the structure of ZrO2 with an un‐symmetric porous microstructure is superior to symmetric one and that, ignoring the influence of temperature dependent properties, the effects of thermo‐mechanical coupling can be ignored if the imposed heat flux density is less than 4 WM/m2.
KNbO 3 films were prepared on Si (100) substrates by pulsed laser deposition. The effect of experimental parameters on the films structure and composition was investigated. Well crystallized and single-phase KNbO 3 fi...
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KNbO 3 films were prepared on Si (100) substrates by pulsed laser deposition. The effect of experimental parameters on the films structure and composition was investigated. Well crystallized and single-phase KNbO 3 films were obtained at the substrate temperature of 650 °C, laser energy of 7.5 mJ/pulse and target-substrate distance of 40 mm, but a severe potassium-deficient was observed in the deposited films. The mechanism of K deficiency in films was explored and a method to control the composition was designed. The experimental results indicate that the composition of films can be well controlled by adjusting the oblique angle of substrates from the axial direction of plume. The stoichiometric KNbO 3 films with K/Nb molar ratio of 0.98 were obtained by locating the substrate at an oblique angle of 3–12° from the plume axis.
To reuse roller waste as a raw material of high performance green ceramic balls, three kinds of white alumina ceramic balls whose wear resistance were 2-3 times of the best high alumina ceramic ball with 90% Al2O3 wer...
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To reuse roller waste as a raw material of high performance green ceramic balls, three kinds of white alumina ceramic balls whose wear resistance were 2-3 times of the best high alumina ceramic ball with 90% Al2O3 were prepared, and the Al2O3 content of the prepared balls was 75%. It is found that the effect of calcia and magnesia on the wear resistance of ceramic balls is contrast to the accepted one： the wear rate of the ceramic balls prepared in CaO-Al2O3-SiO2 system is the lowest and the wear rate of the ceramic balls prepared in MgO-Al2O3-SiO2 is the highest. The main crystal phase of the ceramic ball is mullite and corundum. The ceramic ball granular is uniform and fine with 4-5 μm average size. The pore diameter is about 2 μm. The wear way of the ceramic balls is mainly transcrystalline fracture.
The air plasma spray (APS) technology was used to prepare WC/NiCrAl and WC/NiCrBSi ceramic/metal composite wear preventive coating on cast iron substrate. The microstructure, microhardness, bond strength and slurry we...
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The air plasma spray (APS) technology was used to prepare WC/NiCrAl and WC/NiCrBSi ceramic/metal composite wear preventive coating on cast iron substrate. The microstructure, microhardness, bond strength and slurry wear preventive performance of coating was measured. The results revealed that all of the coating prepared by APS has good qualities. The coating with NiCrBSi as its combining metal is better than that with NiCrAl on wear preventive performance, and coating containing more WC is supreme than that containing less WC Finally, wear mechanics and the principle of the coating's wear preventive property was concluded.
In this paper the inflaming retarding effects of epoxy resins blended with basic magnesium carbonate [Mg(OH)2·4MgCO3·5H2O] were synthesized. When the add-on of basic magnesium carbonate reached 56.5%, the LO...
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In this paper the inflaming retarding effects of epoxy resins blended with basic magnesium carbonate [Mg(OH)2·4MgCO3·5H2O] were synthesized. When the add-on of basic magnesium carbonate reached 56.5%, the LOI of the epoxy resins increased to 29.7%. The flame retardant mechanisms of basic magnesium carbonate for epoxy resins was investigated by XRD, TG-DSC and SEM. Results showed that through the ways of diluting, cooling, isolating and their synergies, basic magnesium carbonate achieves the flame retarding target.
It is very difficult to prepare full-densified aluminum nitride-boron nitride （AIN/BN） composite ceramics with homogeneous microstructure and high thermal conductivity. Spark plasma sintering （SPS） was used to ful...
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It is very difficult to prepare full-densified aluminum nitride-boron nitride （AIN/BN） composite ceramics with homogeneous microstructure and high thermal conductivity. Spark plasma sintering （SPS） was used to fully densify the AIN/BN composites in this work. Microstructure, mechanical properties and thermal conductivity of the SPS sintered AIN/BN composites with 5-30 vol% BN were investigated. The results show that the microstructure of composites is fine and homogenous, and the AIN/BN composites exhibit high mechanical properties. To promote the growth of AIN grains and modify the distribution of grain boundary in AIN/BN composites, a heat treating methodology was introduced through gas pressure sintering （GPS）. This processing was significantly beneficial to enhancing the thermal conductivity of the specimen. The thermal conductivity of AIN/BN composites with 5-30 vol% BN reached 60 W/m K after the samples were treated by GPS.
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