摘要:
Crack-free alumina honeycombs of high strength and high surface area are made from anhydrous alumina powder extrusion batches incorporating a combination of a hydrous aluminum oxide or aluminum hydroxide permanent binder and a polymeric aluminum salt; extruded honeycombs incorporating these constituents plus temporary binders, peptizing aqueous acid additions and water exhibit significantly reduced drying shrinkage, and thus reduced cracking, high fired surface area, and high fired strength.
摘要:
There is provided a ceramic member for semiconductor manufacturing equipment which is formed of an alumina-based sinter containing an yttrium-aluminum-garnet at the amount of 3 to 50 wt %, silicon oxide at the amount of not more than 0.2 wt %, preferably 0.1 wt %, and the balance substantially alumina, wherein the sinter has dielectric loss of not more than 4null10null4 particularly 2.5null10null4 or less in the frequency range of 10 MHz to 5 GHz. Such a member may be formed of a ceramic sinter including an aluminum phase having mean crystal grain size in a range of 2 to 10 nullm and a yttrium-aluminum-garnet phase having a mean crystal grain size in a range of 1.5 to 5 nullm, wherein the ratio of the mean crystal grain size of the alumina phase to that of the yttrium-aluminum-garnet phase is larger than 1 and smaller than 7.
摘要:
A microstructured or nanostructured multi-component ceramic comprises (a) a major ceramic phase comprising a ceramic oxide composite; (b) a ceramic oxide additive; and (c) a rare earth ceramic oxide additive, wherein the total of the additives (b) and (c) comprise from about 0.1 weight percent to less than 50 weight percent based on the total weight the multi-component ceramic composite. In another embodiment, a microstructured or nanostructured multi-component ceramic comprises (a) a major ceramic oxide phase comprising a ceramic oxide composite; and either (b) a ceramic oxide additive or (c) a rare earth ceramic oxide additive, wherein amount of the additive (b) or (c) comprises from about 0.1 weight percent to less than 50 weight percent based on the total weight the multi-component ceramic composite. Such ceramics are useful as bulk materials or as feedstocks for thermal spray.
摘要:
The disclosed invention relates to novel crystalline compositions which may be obtained by doping the alpha (null) form of AlPO4 ceramics, which find use as piezoelectric materials, stable supports for catalysts, biotechnology uses, and the like.
摘要:
A method of making a component of a ceramic discharge chamber comprising the steps of forming a ceramic composition including an aluminum powder, a binder and a grain growth inhibitor. The alumina powder has a tap density greater than 1.0 gram per cc. The ceramic composition is then die pressed to form a component preform. Next, the component preform is heated to remove at least a substantial portion of the binder.
摘要:
An alumina sintered compact includes at least two layers including an internal layer and a surface layer formed on the surface of the internal layer, which internal layer is composed of alumina crystal grains formed by sintering of a fine alumina powder, and which surface layer is composed of alumina crystal grains formed by grain growth of a fine alumina powder and having a mean grain size larger than that of the alumina crystal grains of the internal layer. This alumina sintered compact can prevent the accumulation of PbO in a surface area while controlling the absorption of PbO.
摘要:
This invention pertains to product and process. The product is a transparent product of a density in excess 99.5% comprising spinel and having uniform mechanical properties. The process pertains to fabrication of a transparent spinel product comprising the steps of dissolving a sintering aid in water to form a neutral sintering aid solution, adding a suitable additive to the sintering aid solution, applying the sintering aid solution to spinel particles to form a spinel dispersion, sub-dividing or atomizing the spinel dispersion to form droplets comprising one or more spinel particles coated with the final spinel solution, drying the droplets to form dried coated particles comprising one or more spinel particles coated with a dried layer of the sintering aid, and densifying the dried coated particles to form a transparent spinel product having uniform optical and mechanical properties in absence of grains of exaggerated size.
摘要:
A method for making an aluminum oxide (Al2O3) component utilizes an amount of aluminum oxide in particle form. The aluminum oxide initially has less than about 100 parts per million of sodium and less than about 600 parts per million of silica. The aluminum oxide is ground with media that comprise aluminum oxide ceramic pieces that have less than about 200 parts per million of sodium to deagglomerate and reduce the particle size of the aluminum oxide. The ground aluminum oxide is placed into a slurry, and a low sodium grade binder is added to the slurry. The slurry is dried to provide an aluminum oxide powder having a sodium content that is less than about 200 parts per million. The powder may then be formed into a certain shape and thermally treated to produce an aluminum oxide component having a low sodium and low silica content.
摘要翻译:制造氧化铝(Al 2 O 3)成分的方法使用一定量的粒子状氧化铝。 氧化铝最初具有少于约100ppm的钠和小于约600ppm的二氧化硅。 用包含氧化铝陶瓷片的介质研磨氧化铝,其具有少于约200ppm的钠以解聚,并降低氧化铝的粒度。 将研磨的氧化铝置于浆液中,向浆料中加入低钠级粘合剂。 将浆料干燥以提供钠含量小于约百万分之200的氧化铝粉末。 然后可以将粉末形成一定形状并进行热处理以产生具有低钠和低二氧化硅含量的氧化铝组分。
摘要:
A novel multipurpose mineral composition capable of emitting a large quantity of far infrared rays, negative ions and oxygen heat is manufactured by setting up an iron railing, an iron rod and an iron plate on a brazier, placing a tinfoil on the iron plate, and layering yellow soil, kaolin, sericite, and biomineral in sequence on the tinfoil, while inserting the tinfoil between the layers, loading a pulverized elvan in the furnace, pulverizing a mixed stone including 40 wt % of germanium, 15 wt % of true marine, 30 wt % of zeolite, and 15 wt % of franklin, to the particle size under about 44 nullm, and loading the pulverized mixed stone in an internal furnace which is made by winding a copper plate with a tinfoil and placed on the plurality of layers of the furnace, heating the pulverized mixed stone at about 1,000null C. for about seven days into a lump, and repulverizing the lump.
摘要:
A polycrystalline translucent aluminum oxide ceramic material having an average grain size of no greater than 1.0 micron and a Contrast Ratio value of less than about 0.7. The material can be in the form of a dental mill blank, dental prosthesis or other dental article or non-dental article.