Abstract: Disclosed herein is a dual density disc comprising a dense outer tube comprising alumina having a purity of greater than 99%; and a porous core comprising alumina of a lower density than a density of the dense outer tube; wherein the porous core has an alumina purity of greater than 99%. Disclosed herein too is method comprising disposing in a dense outer tube a slurry comprising alumina powder and a pore former; heating the dense outer tube with the slurry disposed therein to a temperature of 300 to 600° C. to activate the pore former; creating a porous core in the dense outer tube; and sintering the dense outer tube with the porous core at a temperature of 800 to 2000° C. in one or more stages.

Abstract: Disclosed herein is a dual density disc comprising a dense outer tube comprising alumina having a purity of greater than 99%; and a porous core comprising alumina of a lower density than a density of the dense outer tube; wherein the porous core has an alumina purity of greater than 99%. Disclosed herein too is method comprising disposing in a dense outer tube a slurry comprising alumina powder and a pore former; heating the dense outer tube with the slurry disposed therein to a temperature of 300 to 600° C. to activate the pore former; creating a porous core in the dense outer tube; and sintering the dense outer tube with the porous core at a temperature of 800 to 2000° C. in one or more stages.

Abstract: Sintered fiber filters are provided that can afford high particle capture efficiency and/or low pressure drop during operation, and are useful in applications such as semiconductor processing. The shape of at least a portion of the individual fibers (e.g., metal fibers) used to make the filter have a three-dimensional aspect, which allows for a low packing density and high porosity filtration media. Certain filters have a cylindrical or tube-like shape with tapered ends of higher density. Methods of making such filters, for example, using axial pressing, are also described.

Abstract: A composite structure includes a substrate with pores of a first mean pore size and a coating on at least one surface of that substrate. This coating has pores of a second mean pore size where the first mean pore size is equal to or greater than said second mean pore size. When the pore size of the coating is effective to capture particulate greater than 0.2 micron, the composite may be formed into a filter effective to remove microbes from a fluid medium. One method to form the porous coating on the substrate includes: (1) forming a suspension of sinterable particles in a carrier fluid and containing the suspension in a reservoir; (2) maintaining the suspension by agitation; (3) transferring the suspension to an ultrasonic spray nozzle; (4) applying a first coating of the suspension to the substrate; and (5) sintering the sinterable particles to the substrate.

Abstract: A composite structure includes a substrate with pores of a first mean pore size and a coating on at least one surface of that substrate. This coating has pores of a second mean pore size where the first mean pore size is equal to or greater than said second mean pore size. When the pore size of the coating is effective to capture particulate greater than 0.2 micron, the composite may be formed into a filter effective to remove microbes from a fluid medium. One method to form the porous coating on the substrate includes the steps of: (a) forming a suspension of sinterable particles in a carrier fluid and containing the suspension in a reservoir; (b) maintaining the suspension by agitation in the reservoir; (c) immersing the substrate in the reservoir; (c) applying a first coating of the suspension to the substrate; (d) removing the substrate with the applied first coating from the reservoir; and (e) sintering the sinterable particles to the substrate thereby forming a coated substrate.

Abstract: Sintered fiber filters are provided that can afford high particle capture efficiency and/or low pressure drop during operation, and are useful in applications such as semiconductor processing. The shape of at least a portion of the individual fibers (e.g., metal fibers) used to make the filter have a three-dimensional aspect, which allows for a low packing density and high porosity filtration media. Certain filters have a cylindrical or tube-like shape with tapered ends of higher density. Methods of making such filters, for example, using axial pressing, are also described.

Abstract: Sintered fiber filters are provided that can afford high particle capture efficiency and/or low pressure drop during operation, and are useful in applications such as semiconductor processing. The shape of at least a portion of the individual fibers (e.g., metal fibers) used to make the filter have a three-dimensional aspect, which allows for a low packing density and high porosity filtration media. Certain filters have a cylindrical or tube-like shape with tapered ends of higher density. Methods of making such filters, for example, using axial pressing, are also described.

Abstract: Sintered fiber filters are provided that can afford high particle capture efficiency and/or low pressure drop during operation, and are useful in applications such as semiconductor processing. The shape of at least a portion of the individual fibers (e.g., metal fibers) used to make the filter have a three-dimensional aspect, which allows for a low packing density and high porosity filtration media. Certain filters have a cylindrical or tube-like shape with tapered ends of higher density. Methods of making such filters, for example, using axial pressing, are also described.

Abstract: A composite structure includes a substrate with pores of a first mean pore size and a coating on at least one surface of that substrate. This coating has pores of a second mean pore size where the first mean pore size is equal to or greater than said second mean pore size. When the pore size of the coating is effective to capture particulate greater than 0.2 micron, the composite may be formed into a filter effective to remove microbes from a fluid medium. One method to form the porous coating on the substrate includes: (1) forming a suspension of sinterable particles in a carrier fluid and containing the suspension in a reservoir; (2) maintaining the suspension by agitation; (3) transferring the suspension to an ultrasonic spray nozzle; (4) applying a first coating of the suspension to the substrate; and (5) sintering the sinterable particles to the substrate.

Abstract: Sintered fiber filters are provided that can afford high particle capture efficiency and/or low pressure drop during operation, and are useful in applications such as semiconductor processing. The shape of at least a portion of the individual fibers (e.g., metal fibers) used to make the filter have a three-dimensional aspect, which allows for a low packing density and high porosity filtration media. Certain filters have a cylindrical or tube-like shape with tapered ends of higher density. Methods of making such filters, for example, using axial pressing, are also described.

Abstract: Sintered fiber filters are provided that can afford high particle capture efficiency and/or low pressure drop during operation, and are useful in applications such as semiconductor processing. The shape of at least a portion of the individual fibers (e.g., metal fibers) used to make the filter have a three-dimensional aspect, which allows for a low packing density and high porosity filtration media. Certain filters have a cylindrical or tube-like shape with tapered ends of higher density. Methods of making such filters, for example, using axial pressing, are also described.

Abstract: A method for forming a porous coating with nanosize pores on a substrate includes the steps of (a) forming a suspension of sinterable particles in a carrier fluid; (b) maintaining the suspension by agitating the carrier fluid; (c) applying a first coating of the suspension to the substrate; and (d) sintering the sinterable particles to the substrate. A thin layer of this nanoporous coating is deposited onto a substrate having micropores. The substrate provides strength and structural support while the properties of the nano powder layer controls flow and filtration aspects of the device. This composite has sufficient strength for handling and use in industrial processes. Since the nano powder layer is thin, the pressure drop across the layer is substantially less than conventional thicker nano powder structures.