Abstract:
A honeycomb structure includes a honeycomb unit. The honeycomb unit includes plural cells, inorganic particles, and at least one of a flake substance, a tetrapod-shaped substance, and a three-dimensional needle-shaped substance. The plural cells extend from a first end face to a second end face of the honeycomb structure along a longitudinal direction of the honeycomb structure. The plural cells are defined by cell walls.
Abstract:
A method of manufacturing a honeycomb structural body includes performing a heat treatment on zeolite particles that have undergone an iron ion-exchange. The heat treatment is performed in a non-oxygenated atmosphere having a temperature within a range of approximately 500° C. through approximately 800° C. to obtain heat-treated zeolite particles. A honeycomb molded body is formed from a raw material including the heat-treated zeolite particles. The honeycomb molded body is fired to manufacture a honeycomb unit. The honeycomb structural body includes the honeycomb unit including plural cells extending from a first end face to a second end face in a longitudinal direction. The plural cells are partitioned by cell walls.
Abstract:
A honeycomb structure of the invention includes ceramic particles and inorganic fibers, and is characterized in that the inorganic fibers satisfy an expression of Aspect Ratio≧Fiber Strength (GPa)/0.3.
Abstract:
The invention relates to a method for producing an in particular porous molded ceramic article, which molded ceramic article is optionally reinforced with fibers and/or a semi-finished textile product such as woven fabric, wherein a powder A and at least one further powder B are suspended in a liquid, after which a molded article is formed from the suspension produced in this manner optionally in combination with fibers and/or a semi-finished textile product and the molded article is optionally sintered. It is provided according to the invention that the powders A and B are suspended approximately at a pH value of the liquid at which a viscosity minimum of the suspension is given, whereby high solids contents in the suspension can be adjusted with low viscosities. This makes possible a rapid production of largely crack-free molded articles with advantageously low-defect structures.
Abstract:
A honeycomb structure includes a honeycomb unit which has zeolite, inorganic binder, and cell walls extending from one end to another end along a longitudinal direction of the honeycomb unit to define cells. An amount of zeolite contained per apparent unit volume of the honeycomb unit is approximately 230 g/L or more. Mathematical formulae [1] and [2] are satisfied when a thickness of the cell walls is defined as X mm and an average pore diameter of a surface of the cell walls observed by a microscope is defined as Y μm: X+0.07≦Y≦X+0.27 [1] approximately 0.15≦X≦approximately 0.35 [2].
Abstract:
A ceramic matrix composite with a ceramic matrix and a gradient layering of coating on ceramic fibers. The coating typically improves the performance of the composite in one direction while degrading it in another direction. For a SiC-SiC ceramic matrix composite, a BN coating is layered in a gradient fashion or in a step-wise fashion in different regions of the article comprising the ceramic. The BN coating thickness is applied over the ceramic fibers to produce varying desired physical properties by varying the coating thickness within differing regions of the composite, thereby tailoring the strength of the composite in the different regions. The coating may be applied as a single layer as a multi-layer coating to enhance the performance of the coating as the ceramic matrix is formed or infiltrated from precursor materials into a preform of the ceramic fibers.
Abstract:
A method is provided for producing a highly porous substrate. More particularly, the present invention enables fibers, such as organic, inorganic, glass, ceramic, polymer, or metal fibers, to be combined with binders and additives, and extruded, to form a porous substrate. Depending on the selection of the constituents used to form an extrudable mixture, the present invention enables substrate porosities of about 60% to about 90%, and enables process advantages at other porosities, as well. The extrudable mixture may use a wide variety of fibers and additives, and is adaptable to a wide variety of operating environments and applications. Additives can be selected that form inorganic bonds between overlapping fibers in the extruded substrate that provide enhanced strength and performance of the porous substrate in a variety of applications, such as, for example, filtration and as a host for catalytic processes, such as catalytic converters.
Abstract:
A porous fibrous honeycomb substrate having an aluminum titanate composition and methods of producing the same are provided herein. Precursors of aluminum titanate are provided in an extrudable mixture that includes fiber materials to form a green honeycomb substrate. When cured, the precursors of aluminum titanate form an aluminum titanate composition, with the fiber materials defining the porous microstructure. Various composite structures including aluminum titanate are provided to form a porous honeycomb substrate that can be configured to be filtration media and/or a catalytic host.
Abstract:
A method is provided for producing a highly porous substrate. More particularly, the present invention enables fibers, such as organic, inorganic, glass, ceramic, polymer, or metal fibers, to be combined with binders and additives, and extruded, to form a porous substrate. Depending on the selection of the constituents used to form an extrudable mixture, the present invention enables substrate porosities of about 60% to about 90%, and enables process advantages at other porosities, as well. The extrudable mixture may use a wide variety of fibers and additives, and is adaptable to a wide variety of operating environments and applications. Additives can be selected that form inorganic bonds between overlapping fibers in the extruded substrate that provide enhanced strength and performance of the porous substrate in a variety of applications, such as, for example, filtration and as a host for catalytic processes, such as catalytic converters.
Abstract:
A method is provided for extruding and curing a highly porous substrate. More particularly, the present invention enables fibers, such as organic, inorganic, glass, ceramic, polymer, or metal fibers, to be mixed and extruded to form a highly porous substrate. Depending on the particular mixture, the present invention enables substrate porosities of about 60% to about 90%, and enables process advantages at other porosities, as well. The extrudable mixture may use a wide variety of fibers and additives, and is adaptable to a wide variety of operating environments and applications. Fibers, which have an aspect ratio greater than 1, are selected according to substrate requirements, and are mixed with binders, pore-formers, extrusion aids, and fluid to form a homogeneous extrudable mass. The homogeneous mass is extruded into a green substrate. The more volatile material is preferentially removed from the green substrate, which allows the fibers to interconnect and contact. As the curing process continues, fiber to fiber bonds are formed to produce a structure having a substantially open pore network. The resulting porous substrate is useful in many applications, for example, as a substrate for a filter, a catalyst host, a heat exchanger, a muffler, or a catalytic converter.