Abstract:
An environmental barrier coating material comprising one or more constituents selected from a group consisting of hafnia; hafnia stabilized by one or more rare-earth oxides and/or silica; zirconia-containing hafnia; and zirconia-containing hafnia stabilized by one or more rare-earth oxides and/or silica, which when formed as a coating structure for covering a substrate which has a low thermal expansion coefficient, has hafnon (HfSiO4) serving as a first layer directly formed on the substrate, and hafnia with which the first layer is coated as a second layer.
Abstract:
The present invention relates to a silicon carbide-boron nitride composite material, which synthesised according to an in-situ chemical reaction between silicon nitride, boron carbide and carbon, and which contains fine boron nitride particles dispersed in a silicon carbide matrix, wherein aforementioned composite material is obtained by molding a powder mixture containing each of the components required in the in-situ reaction and sintering the mixture.
Abstract:
The present invention provides a needle-shaped ceramic body and needle-shaped ceramic catalyst body in which a case material is a high specific surface area porous cordierite body that is stable at high temperatures, and also provides methods of producing this needle-shaped ceramic body and needle-shaped ceramic catalyst body. The present invention relates to a needle-shaped ceramic body and needle-shaped ceramic catalyst body in which a base material is a high temperature-stable, high specific surface area porous cordierite body comprising a porous structure having a prescribed porosity and formed of a needle-shaped cordierite crystal phase and further relates to methods of producing this needle-shaped ceramic body and needle-shaped ceramic catalyst body, and by using porous cordierite constituted of needle-shaped crystals as a catalyst-supporting honeycomb structure, the present invention is able to inhibit sintering-induced reduction in the specific surface area. Since a honeycomb can be directly produced as the cordierite sinter itself, an inexpensive product can be provided through the simplifying the prior-art step of coating the interior of the honeycomb.
Abstract:
An environmental barrier coating material comprising one or more constituents selected from a group consisting of hafnia; hafnia stabilized by one or more rare-earth oxides and/or silica; zirconia-containing hafnia; and zirconia-containing hafnia stabilized by one or more rare-earth oxides and/or silica, which when formed as a coating structure for covering a substrate which has a low thermal expansion coefficient, has hafnon (HfSiO4) serving as a first layer directly formed on the substrate, and hafnia with which the first layer is coated as a second layer.
Abstract:
The present invention relates to porous calcium zirconate/magnesia composites having a thermally and chemically stable porous structure, which consist of sintered compacts having a fine composite structure stable under high temperatures due to uniformly dispersed equimolar amounts of calcium zirconate [CazrO3] and magnesia [MgO] and controlled grain growth, and a method of producing the same, and the present porous composites are useful as, for instance, a functional material for filtering highly corrosion resistant materials, lightening members used at super-high temperatures, catalyst carriers, insulation or sound-absorbing materials, and the like.
Abstract:
The present invention provides a needle-shaped ceramic body and needle-shaped ceramic catalyst body in which a base material is a high specific surface area porous cordierite body that is stable at high temperatures, and also provides methods of producing this needle-shaped ceramic body and needle-shaped ceramic catalyst body. The present invention relates to a needle-shaped ceramic body and needle-shaped ceramic catalyst body in which a base material is a high temperature-stable, high specific surface area porous cordierite body comprising a porous structure having a prescribed porosity and formed of a needle-shaped cordierite crystal phase, and further relates to methods of producing this needle-shaped ceramic body and needle-shaped ceramic catalyst body, and by using porous cordierite constituted of needle-shaped crystals as a catalyst-supporting honeycomb structure, the present invention is able to inhibit sintering-induced reduction in the specific surface area. Since a honeycomb can be directly produced as the cordierite sinter itself, an inexpensive product can be provided through the simplifying the prior-art step of coating the interior of the honeycomb.
Abstract:
This invention relates to a method of producing an alumina porous material using a mixed powder of alumina powder and aluminum hydroxide represented by the chemical formula Al(OH)3 at different percentages as the starting material, comprising the steps of heating this mixed powder to decompose the aluminum hydroxide and further heat treating it within a temperature range of 1,000 to 1,600° C., and to the alumina porous material produced by the above-mentioned method with a porosity exceeding 40 volume % and its specific surface area of 8 to 40 m2/g, and further to a filter and catalyst carrier that are obtained using this alumina porous material.