Showing papers in "Ceramics International in 2001"

TL;DR: The potential and limits of rice husk to prepare relatively pure activated silica were investigated in this paper, where a chemical pre-and post-treatment using HCl, H2SO4 and NaOH solutions.

TL;DR: In this article, the thermal behavior of a Bio kaolin raw material (Bio) containing mainly well-crystallised kaolinite and muscovite minerals was studied in relation to heating rate, from 3 to 20°C min −1.

TL;DR: In this article, the effect of ground active silica obtained from rice husk ash (RHA) in traditional whiteware composition was investigated and the complete replacement of quartz by RHA drastically reduced both the maturing temperature and the percentage of thermal expansion, and increased the strength marginally.

TL;DR: In this paper, a dense MgAl 2 O 4 sintered spinel has been prepared following a conventional double stage firing process, and a new type of sintering aid, AlCl 3, can improve the bulk density, apparent porosity and water absorption of the spinel.

TL;DR: In this article, ammonium carbonate was used as the precipitant to synthesize Mg-Al spinel precursors from a mixed solution of magnesium and aluminum nitrates.

TL;DR: In this paper, aqueous and mixed ethyl alcohol-water solution of CeCl 3 and GdCl 3 on Ni foil and Ni-yttria stabilized zirconia substrates was studied.

TL;DR: In this paper, a gelled mixture of kaolinite and aluminum hydroxide was used to fabricate porous mullite ceramics with open porosity of 58.5-63.9%, mean pore size of 0.76-1.31 μm, and nitrogen permeability of 526-1240 m3 m−2 bar−1 h−1

TL;DR: In this paper, the CaO-Al2O3 system was studied by differential thermal analysis method in content interval from 0 to 60 mass% CaO. The absence of congruently melting compounds in argon atmosphere was confirmed and the coordinates of eutectic and peritectic points redefined.

TL;DR: In this article, the role of dispersant and powder dimension on the slurry rheology and the corresponding effect on green as well as sintered densities of tape cast yttria stabilized zirconia (YSZ) was investigated.

TL;DR: In this article, the use of an incinerator fly ash of municipal solid wastes (MSW) and two different granite sawing residues in the obtaining of new types of porcelainized stoneware was investigated.

TL;DR: In this article, a novel synthesis process was developed for producing high purity nonagglomerate nano plate-like α-Al 2 O 3 particles, which mainly utilizes a seed effect of fine α-al 2O 3 grains worn from the milling mediums and uniformly mixed with the hydrous alumina during grinding, and also utilizes ZnF 2 additive to reduce the transformation temperature and modify the alumina particle shape.

TL;DR: In this paper, the effect of Y2O3 and Yb 2 O3 on the microstructure and mechanical properties of silicon nitride was investigated, and the effects of heat treatment on the crystallization of grain boundary phases and on the high-temperature strength was also studied.

TL;DR: In this paper, a technique for the sintering of yttria stabilised cubic zirconia is described, and a significant advantage in terms of higher density of the ceramics at lower heat work is noted compared to the conventional radiant heat fired products.

TL;DR: In this paper, a series of oxides Ca3−xSrxCo4O9+δ, (x=0.0, 1.0) were synthesized, and their structures, electrical properties and Seebeck coefficients were measured from room temperature to 700°C.

TL;DR: In this paper, the effect of the mullite bond phase on the physico-mechanical and refractory properties of the castable castables was investigated after firing at different firing temperatures using X-ray diffractin analysis.

TL;DR: In this paper, structural and electrical properties of ZnO varistors were investigated as a function of spinel composition, and the results showed significant difference in electrical properties: nonlinearity coefficients ranging from 22 to 55 and leakage currents differing by the order of magnitude.

TL;DR: The phase stabilities of plain and CuO-doped 2.5 mol% Y-TZP ceramics, sintered at 1300°C, were investigated by exposure in hostile environments for periods of up to 2000 h.

TL;DR: A feasibility study of laser clad 7 wt.% yttria partially stabilized zirconia ceramic coatings undoped or doped with 2.5 wt% TiO 2 to produce single tracks and partially overlapped tracks on the surfaces of AlSi9Cu3, AlZn10Si8Mg and AlSi10Mg alloys was carried out by using a 6 kW RS5000 continuous wave CO 2 laser together with continuous powder-feeding system as mentioned in this paper.

TL;DR: In this paper, the microstructure of the as-prepared WC-Co coatings was determined with SEM, TEM and XRD, and the results showed that the main structure of the coatings is composed of WC grains with a mean particle size of 35 nm, which have a similar grain size to the primary powders.

TL;DR: In this paper, the conditions of thermodynamic equilibrium for the chemical reactions occurring in the studied system during sintering were calculated and used to explain the formation of the graded porosity.

TL;DR: In this article, theoretical and experimental studies on the CBN-TiC 1:1 molar ratio were presented, and it was shown that TiC reacts with boron nitride forming two new phases, TiB2 and TiN.

TL;DR: In this article, the results of using three simple glass systems including PbO-B2O3, PbBO-SiO2, and Bi2O2-O3 as sintering aids for hydrothermal synthesized BaTiO3 were employed.

TL;DR: In this article, the extrusion characteristics of alumina pastes involving boehmite gel as a binder are reported and the paste rheology, workability, green strength and sintered properties are studied and reported.

TL;DR: In this paper, the authors examined the friction coefficient and wear rates of ceramic composites with different volume fraction of SiC whisker, and their friction and wear behavior sliding against cemented carbide at temperatures up to 800°C in air and nitrogen atmospheres has been studied.

TL;DR: In this article, an ion exchange and sintering of low silica zeolites prepared from commercially available china clay has been investigated and the effect of rate of heating on the properties of the sintered products was also investigated.

TL;DR: In this paper, the synthesis of alumina/silicon carbide composites by self-propagation reactions activated by Teflon is investigated, and it is shown that small amounts of this material (i.e. 0.20-0.25 wt.%) guarantee the occurrence of self propagation reactions leading to the formation of a composite.

TL;DR: In this paper, a nanocomposite SiC powder was prepared by coating nano-SiC particles with Y(OH) 3 and/or Al(OH 3 via heterogeneous nucleation processing using a buffered pH solution as the precipitation reagent.

TL;DR: In this article, a slip casting and subsequent pressureless sintering route has been revealed as a powerful method to obtain a high-density silicon nitride material, and the optimisation of the slip casting preparation and of the sinterings conditions has been investigated.

TL;DR: In this paper, the sinterability of two different ceramic wastes coming from the hydrometallurgy processing of zinc ores was investigated in view of their low-cost reuse as porous building materials for heat and sound insulation.

TL;DR: In this paper, the microstructures and dielectric properties of Bi(Nb,Ta)O 4 ceramics with different amount of CuO additions were investigated.