Papers by Keyword: Ceramic Fiber

Abstract: Ceramic fiber is a kind of fibrous lightweight refractory with many advantages of light weight, thermostability, good heat stability, low thermal conductivity, small specific heat, and resistance to mechanical vibration and so on. As a result of them, it has been used widely in lots of fields, such as machinery, metallurgy, chemical industry, oil, ceramics, glass and electron. From the aspect of the ceramic fiber development, in this essay, the types and preparation methods of ceramic fiber have been listed one by one, and the author focused on analyzing the development trend of ceramic fiber and the application in papermaking industry.

Abstract: The effect of surface treatment of ceramic fibers on properties of handsheets was discussed. It is indicated with the addtion of ceramic fibers, the tightness of handsheets increases and the tensile index, elongation and tear index increase at first and then decrease. The tightness, tensile index, elongation and tear index of handsheets with surface treated ceramic fibers are higher than that with untreated ceramic fibers. The ceramic fibers and paper fibers can interweave into three dimensional networks.

Abstract: Structure, viscosity and crystallization behavior of CaO-MgO-SiO₂ ceramic fiber with Nd₂O₃ were investigated by DTA, XRD and FTIR techniques. The results show that the addition of Nd₂O₃ enhanced the fiberization by extending the viscosity curve of the glass melt to lower temperature and improved the melt fiberizability. With the reinforcement of silicate glass network by Nd³⁺, the precipitation of crystals in fibers was inhibited at high temperatures.

Abstract: Full-automatic concrete pressure machine and 100-mm-diameter split Hopkinson pressure bar (SHPB) apparatus were used to investigate quasi-static and dynamic energy absorption property of ceramic fiber reinforced concrete (CRFRC) subjected to various high strain rates, which is compared to carbon fiber reinforced concrete at the same volume fraction of 0.1%, 0.2% and 0.3%. And the absorbing mechanism of CRFRC is analyzed. The results show that the quasi-static energy-absorption property of CRFRC increases with the volume of ceramic fiber and the relation presents linear approximations; the specific energy absorption of ceramic fiber reinforced concrete is strain rate-dependent dynamic strength-dependent under impact load, and the effect can be expressed by linear approximations. And the strain rate is more distinct when volume fraction of ceramic fiber increases. The energy absorption property of ceramic fiber reinforced concrete is superior to plain and carbon fiber reinforced concrete, especially at higher strain rate and volume.

Abstract: Melt spinnable silicone resin with a low carbon content was spun to fiber form with an averaged diameter of 16.8 m. When the resin fiber was cured by SiCl4 vapor and pyrolyzed at 1273K in inert atmosphere, Si-O-C fiber with smooth surface was obtained. The measured tensile strength was relatively low. The fiber, however, showed oxidation resistance during high temperature exposure under an air flow. When the fiber was cured by TiCl4 with an increased vapor pressure at 313K, 40% mass gain was observed after the curing. SiO2-TiO2 fiber was obtained by pyrolysis in an air flow, while SiOC-TiO2 fiber was obtained by pyrolysis in an inert atmosphere. Structure of TiO2 and the resulting fiber surface morphology strongly depended on the temperature and the atmosphere during the pyrolysis.

Abstract: Silicon carbide (SiC) based fibers with continuous pore structures were synthesized by the precursor method using a polycarbosilane (PCS) and polymethylhydrosiloxane (PMHS) polymer blends. The pore formation process can be explained by hydrogen gas dissolution in the polymer melt and desaturation process of the dissolved gas during the fiber spinning. We investigated the effect of PMHS additives with different chemical and physical natures on the obtained pore structures, because PMHS decomposition process played a role of hydrogen gas source. The individual polymer melts were characterized by viscosity measurement, gas chromatograph analysis and thermogravimetric (TG) analysis in order to obtain details of pore structure control.

Abstract: Polymethylsilsesquioxane (PMSQ) fiber was exposed to metal chloride vapors in a controlled atmosphere or electron beam irradiation in air to promote the curing process. The cured fibers were pyrolyzed at 1273K to compare the efficiency of individual curing method. The cured fibers were investigated by FT-IR, an optical microscope and TG analysis. In the case of successful curing, averaged diameter and tensile strength were analyzed on the obtained Si-O-C fibers.

Abstract: Three ceramic fibres VK-60, ABK and Nextel/VK-80 produced by the steam blowing and nozzle dissemination methods have been investigated for the effect of press load per unit area and temperatures using the advantageous transient plane source (ATPS) method in air. It was noticed that, with the increase of the aluminium content in the composition of the ceramic fibres, the thermal conductivity of the material decreases and the isolation properties improved. The Nextel/VK-80 fibre has the lowest and VK-60 the highest value of thermal conductivity at room temperature. The application of a press load results in an increase in the value of the thermal conductivity for all the fibres analysed. ABK fibres showed the least increase and Nextel/VK-80 registered an increase of about 10% in the value of thermal conductivity within the load increase from 0.6 to 6.6 kN m−2. However, above 6.6 kN m−2 the thermal conductivity of all the samples increased almost linearly. The thermal conductivity measurements as a function of temperature indicated the same trend for an increase in thermal conductivity for all the samples.

Abstract: The bulk tiles of ceramic fibers reinforced aerogel were prepared from two reinforcements, evenly dispersed ceramic fibers and sintered tiles. It has been found that ceramic fiber-reinforced aerogels showed higher thermal conductivity than aerogel itself. Shrinkage of aerogels in chopped fiber reinforced aerogel composites showed similar tendency as pure aerogel during gelation, but the shrinkage was prohibited during supercritical drying. By contrary, in the case of sintered tile reinforced aerogel, shrinkage of aerogel was completely limited in both gelation and drying processes. Average of about 50% increase of compressive strengths of the sintered tile reinforced aerogel to sintered tiles were obtained with an average density increase of about 36%, their thermal conductivity depressed slightly.

Abstract: In order to assess the behavior of ceramic fibers that are respired and accumulate in the lung, the solubility of bio-soluble CaO-MgO-SiO2 system ceramic fibers was determined by measuring the concentrations of the main components in the Gamble solution after different solution periods. The effect of ZrO2, TiO2, B2O3, Al2O3 and the different CaO/MgO ratio of fibers on the solubility of the ceramic fibers were investigated. The results indicated that the pH value of the Gamble solutions increase with the increasing of solution time. CaO, MgO, SiO2 in the ceramic fiber have greater solubility. The existence of ZrO2 and Al2O3 in the fibers would reduce the solubility of the fibers, and the existence of TiO2, and B2O3 in fibers will benefit the solubility of the fibers.