Abstract: A membrane for use in a high temperature gas processing system and method for making the same. The membrane includes a dense, gas impermeable layer and a first and second porous layer, wherein each of the first and second porous layers is a ceramic oxide material having a non-symmetrical load bearing skeleton of a plurality of pores having a graded porosity. Each porous layer provides a reduction of an oxygen partial pressure gradient across the dense layer and reduces resultant stresses in the dense layer that are small compared to its strength thereby improving long term mechanical durability of the dense layer.

Abstract: A membrane for use in a high temperature gas processing system and method for making the same. The membrane includes a dense, gas impermeable layer and a first and second porous layer, wherein each of the first and second porous layers is a ceramic oxide material having a non-symmetrical load bearing skeleton of a plurality of pores having a graded porosity. Each porous layer provides a reduction of an oxygen partial pressure gradient across the dense layer and reduces resultant stresses in the dense layer that are small compared to its strength thereby improving long term mechanical durability of the dense layer.

Abstract: A hybrid armor architecture is provided that is effective against explosively-formed and other high-energy ballistic projectiles. The architecture includes at least one laminate reactive armor panel including a layer of non-explosively reactive material sandwiched between outer layers of a ductile material, an armor plate disposed behind the laminate reactive armor panel, and a flyer plate disposed behind the armor plate. The flyer plate or a portion thereof is configured to move toward and impact a body panel that is being protected on impact of a high-energy ballistic projectile with the flyer plate or the portion thereof, to thereby increase the total area of impact with the body panel relative to the projectile alone.

Abstract: Affixable armor that can be used to provide additional protection for a surface is described. The affixable armor includes polygonal ceramic tiles that can be attached directly to a surface, or first attached to a carrier sheet which is then attached to a surface. A visco-elastic polymer can be used to help absorb projectile impact. The ceramic tiles include a substantially conical or pyramidal deflecting front surface to provide additional protection. The ceramic tiles can be placed so that they are spaced to provide a gap with a width that is less than the diameter of an expected ballistic threat in order to provide additional projection. The affixable armor can be configured for rapid removal and replacement, or it may be permanently affixed to the surface.

Abstract: A method of forming a pyrolytic boron nitride (PBN) article and an article having layers of PBN separated by layers of PBN having a dopant of sufficient concentration to induce peeling, the steps of introducing vapors of ammonia and a gaseous boron halide in a suitable ratio into a heated furnace reactor to cause boron nitride to be deposited in layers on a substrate, with at least one gaseous dopant injected into furnace at controlled periodic interval(s) such that at least two selected layers of boron nitride are doped with said gaseous dopant(s) at a minimum average concentration of 0.1 atomic wt % at a depth ranging from 1000 to 2000 angstroms in each selected layer, and with the selected layers spaced apart about 0.1 micron to 100 microns.

Abstract: An exhaust manifold is provided having ceramic inner layer that is highly resistant to cracking from thermal cycling. In a preferred embodiment, the ceramic inner layer is slip cast from a slip composition having a major amount of fused silica which has an amorphous structure. The manifold also has a ceramic insulation layer, a strain isolation layer and an outer structural layer in various embodiments. According to one embodiment, the strain isolation layer is provided in the form of an intumescent mat that expands on heating and contracts on cooling up to a certain crossover temperature, above which it loses the ability to contract on cooling. In a preferred embodiment, a catalyst-coated support body is provided in the exhaust manifold. As exhaust gases pass through the manifold, noxious components of the exhaust gases begin to convert to environmentally benign species via the catalyst prior to reaching the catalytic converter. Methods of making an exhaust manifold also are provided.

Abstract: A method of forming a pyrolytic boron nitride (PBN) article and an article having layers of PBN separated by layers of PBN having a dopant of sufficient concentration to induce peeling, the steps of introducing vapors of ammonia and a gaseous boron halide in a suitable ratio into a heated furnace reactor to cause boron nitride to be deposited in layers on a substrate, with at least one gaseous dopant injected into furnace at controlled periodic interval(s) such that at least two selected layers of boron nitride are doped with said gaseous dopant(s) at a minimum average concentration of 0.1 atomic wt % at a depth ranging from 1000 to 2000 angstroms in each selected layer, and with the selected layers spaced apart about 0.1 micron to 100 microns.

Abstract: An exhaust manifold is provided having substantially ceramic inner and insulation layers. The manifold preferably has a metal outer structural layer to impart strength to the manifold. The ceramic layers are made of ceramic fibers with the interstitial spaces between the fibers being filled with ceramic filler material. The preferred ceramic fibers are aluminosilicate fibers. The preferred ceramic filler material is alumina, silica, glass-ceramic or other metal oxide. A method of making an exhaust manifold having a substantially ceramic inner and insulation layer is also provided.

Abstract: A method of forming a pyrolytic boron nitride (PBN) article and an article having layers of PBN separated by layers of PBN having a dopant of sufficient concentration to induce peeling, the steps of introducing vapors of ammonia and a gaseous boron halide in a suitable ratio into a heated furnace reactor to cause boron nitride to be deposited in layers on a substrate, with at least one gaseous dopant injected into furnace at controlled periodic interval(s) such that at least two selected layers of boron nitride are doped with said gaseous dopant(s) at a minimum average concentration of 2 atomic wt % at a depth ranging from 1000 to 2000 angstroms in each selected layer, and with the selected layers spaced apart about 0.1 micron to 100 microns apart.

Abstract: An exhaust manifold is provided having substantially ceramic inner and insulation layers. The manifold preferably has a metal outer structural layer to impart strength to the manifold. The ceramic layers are made of ceramic fibers with the interstitial spaces between the fibers being filled with ceramic filler material. The preferred ceramic fibers are aluminosilicate fibers. The preferred ceramic filler material is alumina, silica, glass-ceramic or other metal oxide. A method of making an exhaust manifold having a substantially ceramic inner and insulation layer is also provided.

Abstract: A method of forming a pyrolytic boron nitride (PBN) article and an article having layers of PBN separated by layers of PBN having a dopant of sufficient concentration to induce peeling, the steps of introducing vapors of ammonia and a gaseous boron halide in a suitable ratio into a heated furnace reactor to cause boron nitride to be deposited in layers on a substrate, with at least one gaseous dopant injected into furnace at controlled periodic interval(s) such that at least two selected layers of boron nitride are doped with said gaseous dopant(s) at a minimum average concentration of 2 atomic wt % at a depth ranging from 1000 to 2000 angstroms in each selected layer, and with the selected layers spaced apart about 0.1 micron to 100 microns apart.

Abstract: A porous ceramic body of high structural strength and integrity is disclosed, along with the method of fabricating such, whereby a curable resin and a sinterable ceramic are mixed and then admixed to removable pore formers, then consolidated into a green body, the pore formers removed, and sintered into the porous ceramic body.

Abstract: A method of manufacturing a molten metal-resisting ceramic fiber composition includes mixing ceramic fibers, a frit, ceramic additives, a low temperature binder, and water. The mixture is formed into a desired shape, preferably by being extruded through a die. The shaped mixture is baked at low temperature, and then is fired at high temperature. During firing, the low temperature binder is oxidized and the frit is melted so as to substantially coat the fibers and fuse them into a porous matrix.

Abstract: A porous ceramic body of high structural strength and integrity is disclosed, along with the method of fabricating such, whereby a curable resin and a sinterable ceramic are mixed and then admixed to removable pore formers, then consolidated into a green body, the pore formers removed, and sintered into the porous ceramic body.

Abstract: A process for the manufacture of high purity, ultra-fine aluminum nitride powder by the carbo-nitridization of alumina. Agglomerates uniform in both size, chemical composition and porosity are formed containing a stoichiometric mixture of alumina and carbon with the addition of a small amount of catalyst. The agglomerates are furnaced in a controlled manner in a well-mixed reaction vessel to achieve a uniform and consistent level of conversion. Milling of the as-reacted agglomerates under a controlled atmosphere will produce high purity, micron sized aluminum nitride powder.

Abstract: The filtration of molten ferrous metal is accomplished by providing a porous ceramic filter preferably comprising particles of alumina and partially stabilized zirconia that are spaced by interconnected cells to form circuitous and tortuous pathways throughout the ceramic body. The filter is a disc-like structure that can have different surface configurations such as corrugations or a waffle design. The filter can be flat-surfaced with an array of cylindrical openings or counterboard openings extending completely through the filter, or with openings extending partially into the filter from the upper and lower sides of the filter. Several relatively thin filters can be arranged in tandem, if desired.

Abstract: The filtration of molten ferrous metal is accomplished by providing a porous ceramic filter preferably comprising particles of alumina and partially stabilized zirconia that are spaced by interconnected cells to form circuitous and tortuous pathways throughout the ceramic body. The filter is a disc-like structure that can have different surface configuration such as corrugations or a waffle design. The filter can be flat-surfaced with an array of cylindrical openings or counterbored openings extending completely through the filter, or with openings extending partially into the filter from the upper and lower sides of the filter. Several relatively thin filters can be arranged in tandem, if desired.

Abstract: A method of manufacturing a molten metal-resisting ceramic fiber composition includes mixing ceramic fibers, a frit, ceramic additives, a low temperature binder, and water. The mixture is formed into a desired shape, preferably by being extruded through a die. The shaped mixture is baked at low temperature, and then is fired at high temperature. During firing, the low temperature binder is oxidized and the frit is melted so as to substantially coat the fibers and fuse them into a porous matrix.

Abstract: The invention relates to the production of desirably consolidated high purity refractory metal borides, carbides, nitrides, or mixtures, combinations of cermets thereof. In the preparation, a second stage reaction is conducted at reduced pressure and sintering temperature. Furthermore, it is carried out in the presence of sintering aid which can be initially present as a particulate material and, as such, may be incorporated with other reaction ingredients. Sintering aid, in a dual role, may serve not only as an assistant in the second stage reaction, but also as a reaction participant. Moreover, during such rection at sintering conditions, the sintering assistance is obtained by means of sintering aid vapor. High purity products of desirable microstructure can be achieved, having densities on the order of 90 percent or more.

Abstract: A component for an aluminum production cell comprising a refractory matrix having a rigid porous structure substantially filled with aluminum.