Abstract: A cordierite honeycomb structure having a coefficient of thermal conductivity of not less than 0.035 J/cm..degree.K.sec, a porosity of not more than 16%, and a coefficient of thermal expansion of not more than 1.0.times.10.sup.-6 /.degree.C. at 40 to 800.degree.0 C. is described. A process for producing a cordierite honeycomb structures, involves at least the steps of: mixing powders of kaolin, talc, and other starting materials for cordierite together so as to provide a chemical composition of cordierite; extruding the mixture; and firing the extrudate, wherein the kaolin has an average particle diameter of not more than 5 .mu.m and such a particle size distribution that the proportion of particles with diameters of less than 1 .mu.m is 10% by weight and the talc has an average particle diameter of not more than 10 .mu.m and such a particle size distribution that the proportion of particles with diameters of less than 1 .mu.m is not more than 5%.

Abstract: Powder mixtures and a method of forming and shaping the mixtures. The method involves compounding the components of powder materials, binder, solvent for the binder, surfactant, and non-solvent with respect to at least the binder, the solvent, and the powder materials. The non-solvent is lower in viscosity than the binder combined with the solvent. The solvent is present in an amount that is less than the amount that would be present otherwise. The components are mixed and plasticized, and shaped to form a green body. The choice of components results in improved wet green strength in the green body. The method is especially useful for extrusion processing of aqueous binder systems such as water and cellulose ethers and hydrophobic non-solvents, to form structures such as honeycombs. In the body, the ratio, upon subsequent firing, of the isostatic strength to the A-axis strength is at least about 20% higher than in bodies made without the mixture composition of the invention.

Abstract: A cordierite body is produced by providing cordierite-forming raw materials as talc, calcined talc, MgO-forming component, magnesium aluminate spinel, SiO.sub.2 -forming component, Al.sub.2 O.sub.3 -forming component, kaolin, calcined kaolin, and/or mullite, such that the quantity R is less than about 10.156. R is0.140 (wt. % mullite powder)+0.433 (wt. % SiO.sub.2 powder)+0.0781 (wt. % alpha Al.sub.2 O.sub.3 powder)(mean particle size of alpha Al.sub.2 O.sub.3 powder)+0.0872 (wt. % Al(OH).sub.3 powder)(mean particle size of Al(OH).sub.3 powder)+0.00334 (wt. % SiO.sub.2 powder)(wt. % spinel powder)+2.330 log.sub.10 (1+(wt. % MgO-forming component)(wt. % calcined kaolin))-0.244 (wt. % MgO-forming component)-0.167 (wt. % dispersible high surface area Al.sub.2 O.sub.3 -forming component)+1.1305 (heating time at maximum temperature).sup.-1.

Abstract: A method of fabricating a cordierite ceramic honeycomb structural body which includes the following steps: formulating a batch of raw materials comprising a mixture of kaolin clay, talc, alumina and other cordierite-forming materials, each included in the batch in an effective amount such that the batch is capable of yielding a fired honeycomb body whose predominant crystal phase is cordierite; intimately blending the raw materials with an effective amount of vehicle and forming aids to impart plastic formability and green strength to the raw materials and to form a plastic mixture; forming the raw materials into a green honeycomb structural body by extrusion and thereafter drying and firing the green honeycomb structural body. The firing of the green honeycomb structural body is accomplished through a four-phase heating process as follows (1) heating the green body to a first temperature ranging between about 750-850.degree. C.; (2) heating to a second temperature ranging between about 1250 to 1350.degree.

Abstract: A method of firing ceramic honeycomb structural bodies, in which cordierite raw materials including at least raw kaolin is extruded to obtain a honeycomb structural formed body and the thus obtained honeycomb structural formed body is fired. The method includes the step of firing a honeycomb structural body having a rib thickness of not more than 4.6 mil under such a condition that a temperature ascending rate during 400-600.degree. C. is maintained under 70.degree. C./hr. As a preferred embodiment, a temperature ascending rate during 400-600.degree. C. is defined as under 70.degree. C./hr in the case of manufacturing a honeycomb structural body having a rib thickness of 4.6-4.0 mil, or, a temperature ascending rate during 400-600.degree. C. is defined as under 40.degree. C./hr in the case of manufacturing a honeycomb structural body having a rib thickness of 3.9-2.0 mil.

Abstract: A cordierite body is produced by providing cordierite-forming raw materials as talc, calcined talc, MgO-forming component, magnesium aluminate spinel, SiO.sub.2 -forming component, Al.sub.2 O.sub.3 -forming component, kaolin, calcined kaolin, and/or mullite, such that the quantity R is less than about 1.207. R is0.253 (wt. % mullite powder)+0.278(wt. % SiO.sub.2 powder)+0.00590(wt. % SiO.sub.2 powder)(wt. % spinel powder)-0.0193(wt. % SiO.sub.2 powder)(heating time at maximum temperature)-0.348(heating time at maximum temperature)-0.00237(mean heating rate from 25.degree. C. to 1275.degree. C.)+0.0736(wt. % alpha Al.sub.2 O.sub.3 powder)(mean particle size of alpha Al.sub.2 O.sub.3 powder)+0.0892(wt. % Al(OH).sub.3 powder)(mean particle size of Al(OH).sub.3 powder)-0.215(wt. % dispersible high surface area Al.sub.2 O.sub.3 -forming component)+2.392(log.sub.10 (1+(wt. % MgO-forming component)(wt. % calcined kaolin))).

Abstract: There are provided thin-walled honeycomb structural bodies with high strength and excellent thermal shock resistance by using as the starting material for cordierite honeycomb structural bodies a combination of talc with a median particle diameter exceeding 7 .mu.m and not greater than 20 .mu.m and with a CaO content of 0.2 wt % or less and another cordierite material such as kaolin with a median particle diameter of not greater than 1 .mu.m, molding the starting material into a honeycomb shape with a cell wall thickness of 130 .mu.m or less, and firing the mold.

Abstract: A production method of a honeycomb structure is provided. The production method of a thin wall cordierite honeycomb structure having cordierite as the main component of the crystalline phase includes: adding a forming auxiliary agent to a cordierite material to obtain a mixture, kneading the mixture to obtain a material batch, forming the material batch by extrusion to form a honycomb compact, drying the honeycomb compact to obtain a dried body, and firing the dried body. The cordierite material batch contains 65% by weight or more flat plate-like cordierite raw material including crystal water made from talc, kaolin and aluminum hydroxide with the BET specific surface areas for the cordierite raw materials being 7 to 18 m.sup.2 /g of talc, 14 to 22 m.sup.2 /g of kaolin and 6 to 18 m.sup.2 /g of aluminum hydroxide.

Abstract: A method of making a shaped article involves forming an aqueous mixture comprising inorganic powder material, supercritical fluid, organic binder component a portion of which is essentially insoluble in water, and aqueous vehicle, and extruding the mixture into a shaped article.

Abstract: A production method of a cordierite ceramic honeycomb structure is provided. Clay mineral, which is one component in the cordierite material batch for extruding, contains dickite and at least one selected from the group consisting of kaolinite and halloysite, with a 5 to 50% by weight dickite amount in the clay mineral. The honeycomb structure has a thin partition wall, and is suitable for the mass production by improving the formability (in particular, the lubricity and the shape stability) in extruding and by preventing crack generation in the firing process.