Abstract: A method of minimizing the formation of a rhodium-platinum defect in a glass or glass ceramic material or in the melt thereof is provided. The method includes providing a vessel made of a platinum-rhodium alloy for use in a manufacturing process for obtaining the material, and an interface between the vessel and the melt is present. The method can include providing sufficient partial pressures of hydrogen outside and inside the vessel for controlling the partial pressure of oxygen in a region of the melt adjacent to the interface. A method of minimizing the formation of, or counteracting the impact of, a localized thermal, electrical, or composition cell in the melt during a manufacturing process is also provided. The method can include adding a multivalent compound to the melt, adding a mixer to the finer tube, adding a mixing step to the manufacturing process, or amplifying the mixing.

Abstract: An apparatus and method for manufacturing a glass article includes a conduit of precious metal or precious metal alloy hat encloses molten glass. The apparatus and method also includes a channel positioned inside or proximate the conduit that flows a defect inhibiting fluid therethrough. The channel includes at least one orifice positioned proximate a free surface of the molten glass from which flows the defect inhibiting fluid.

Abstract: A first method of forming an object (400) includes wrapping foil around a preform (305) to provide a multi-layered structure including a plurality of layers of wrapped foil, and diffusion bonding the plurality of layers and the preform (305) together to form the object (400). A second method of forming an object includes wrapping foil around a preform (305) to provide a multi-layered structure comprising a plurality of layers of wrapped foil, removing the preform (305) from the multi-layered structure, and diffusion bonding the plurality of layers together to form the object (400). A third method of forming an object includes stacking a plurality of layers of foil to provide a multi-layered structure, diffusion bonding the plurality of layers together, and shaping the diffusion bonded multi-layered structure to form the object (400).

Abstract: A glass manufacturing apparatus including a delivery vessel including a body portion with a cylindrical inner surface extending along a central axis of the body portion. In one embodiment, an upper end of the body portion is substantially equal to or lower than an uppermost portion of a travel path in a downstream end of a conduit connected to the delivery vessel. In another embodiment, a central axis of a delivery pipe is offset a distance from the central axis of the body portion of the delivery vessel. In still another embodiment, the delivery vessel includes a conical top including a taper angle from greater than 0° to about 20°. In further embodiments, methods include manufacturing glass with one or any combination of the above-referenced embodiments of glass manufacturing apparatus.

Abstract: A first method of forming an object (400) includes wrapping foil around a preform (305) to provide a multi-layered structure including a plurality of layers of wrapped foil, and diffusion bonding the plurality of layers and the preform (305) together to form the object (400). A second method of forming an object includes wrapping foil around a preform (305) to provide a multi-layered structure comprising a plurality of layers of wrapped foil, removing the preform (305) from the multi-layered structure, and diffusion bonding the plurality of layers together to form the object (400). A third method of forming an object includes stacking a plurality of layers of foil to provide a multi- layered structure, diffusion bonding the plurality of layers together, and shaping the diffusion bonded multi-layered structure to form the object (400).

Abstract: A glass manufacturing apparatus including a delivery vessel including a body portion with a cylindrical inner surface extending along a central axis of the body portion. In one embodiment, an upper end of the body portion is substantially equal to or lower than an uppermost portion of a travel path in a downstream end of a conduit connected to the delivery vessel. In another embodiment, a central axis of a delivery pipe is offset a distance from the central axis of the body portion of the delivery vessel. In still another embodiment, the delivery vessel includes a conical top including a taper angle from greater than 0° to about 20°. In further embodiments, methods include manufacturing glass with one or any combination of the above-referenced embodiments of glass manufacturing apparatus.

Abstract: An apparatus for processing a quantity of glass melt comprises a segmented tube including a first tube segment and a second tube segment. A second end portion of the first tube segment is joined to a first end portion of the second tube segment. In further examples, methods of fabricating a segmented torsion tube include joining together segmented torsion tubes at an integral solid-state joint.

Abstract: Hydrogen may permeate into an interior space of an article in response to molten glass being in contact with the outer surface of the article. The permeation may be restricted by having a fluid in a length of the interior space. The fluid may be in contact with the inner surface of the article, the fluid may fill at least about 33% of the volume of the length of the interior space, and the fluid may provide a predetermined partial pressure of hydrogen. Features may be provided for causing the fluid to flow within the interior space.

Abstract: A precious metal structure which has an internal gas permeable membrane is described herein for a glass manufacturing vessel configured to have molten glass flow therein. The internal gas permeable membrane can be supplied with an atmosphere of gas (or gases) to control the flux of hydrogen into our out of the molten glass or otherwise improve the production of the molten glass. In this manner, the undesirable detrimental reactions that can occur at the interface of the molten glass and precious metal interface which can cause defects in the molten glass such as bubbles or solid inclusions can be stopped or at least substantially reduced.

Abstract: A precious metal structure which has an internal gas permeable membrane is described herein for a glass manufacturing vessel configured to have molten glass flow therein. The internal gas permeable membrane can be supplied with an atmosphere of gas (or gases) to control the flux of hydrogen into our out of the molten glass or otherwise improve the production of the molten glass. In this manner, the undesirable detrimental reactions that can occur at the interface of the molten glass and precious metal interface which can cause defects in the molten glass such as bubbles or solid inclusions can be stopped or at least substantially reduced.

Abstract: A precious metal structure which has an internal gas permeable membrane is described herein for a glass manufacturing vessel configured to have molten glass flow therein. The internal gas permeable membrane can be supplied with an atmosphere of gas (or gases) to control the flux of hydrogen into our out of the molten glass or otherwise improve the production of the molten glass. In this manner, the undesirable detrimental reactions that can occur at the interface of the molten glass and precious metal interface which can cause defects in the molten glass such as bubbles or solid inclusions can be stopped or at least substantially reduced.

Abstract: An apparatus for producing glass ribbon comprises a melting vessel configured to melt a batch of material into a quantity of molten glass. The apparatus includes a cooling conduit with a peripheral wall comprising platinum and defining an interior pathway configured to provide a travel path for the quantity of molten glass traveling from the first conditioning station to the second conditioning station. The peripheral wall includes an outer surface defining a plurality of elongated radial peaks spaced apart by a plurality of elongated radial valleys. The elongated radial peaks and elongated radial valleys are helically wound along an elongated axis of the cooling conduit. In further examples, methods are provided with the step of passing molten glass through the interior pathway of the cooling conduit to pass the molten glass from the first conditioning station to the second conditioning station.

Abstract: Disclosed herein are methods for bonding refractory substrates, such as zircon substrates, without the use of a bonding agent. Exemplary methods include (a) providing a plurality of refractory components, each component having at least one surface to be bonded, (b) polishing each surface to be bonded to a surface roughness (Ra) of 200 nm or finer, (c) contacting the surfaces to be bonded to form an unbonded refractory substrate, (d) firing the unbonded refractory substrate, and (e) subjecting the surfaces to be bonded to a compressive force during firing. Methods for making refractory forming bodies are also disclosed herein.

Abstract: Hydrogen may permeate into an interior space of an article in response to molten glass being in contact with the outer surface of the article. The permeation may be restricted by having a fluid in a length of the interior space. The fluid may be in contact with the inner surface of the article, the fluid may fill at least about 33% of the volume of the length of the interior space, and the fluid may provide a predetermined partial pressure of hydrogen. Features may be provided for causing the fluid to flow within the interior space.

Abstract: Disclosed herein are methods for bonding refractory substrates, such as zircon substrates, without the use of a bonding agent. Exemplary methods include (a) providing a plurality of refractory components, each component having at least one surface to be bonded, (b) polishing each surface to be bonded to a surface roughness (Ra) of 200 nm or finer, (c) contacting the surfaces to be bonded to form an unbonded refractory substrate, (d) firing the unbonded refractory substrate, and (e) subjecting the surfaces to be bonded to a compressive force during firing.

Abstract: A precious metal structure which has an internal gas permeable membrane is described herein for a glass manufacturing vessel configured to have molten glass flow therein. The internal gas permeable membrane can be supplied with an atmosphere of gas (or gases) to control the flux of hydrogen into our out of the molten glass or otherwise improve the production of the molten glass. In this manner, the undesirable detrimental reactions that can occur at the interface of the molten glass and precious metal interface which can cause defects in the molten glass such as bubbles or solid inclusions can be stopped or at least substantially reduced.

Abstract: Stirring apparatuses for stirring molten glass are disclosed. The method includes stirring a molten glass with a stirrer comprising a layer containing at least about 50% iridium. An apparatus comprising an iridium-containing layer is also presented. In one embodiment, an apparatus for stirring molten glass includes a cylinder comprising a bore. A stirrer may be disposed in the bore. The stirrer may include a platinum or platinum alloy shaft coaxial with the cylinder. A plurality of impellers may project radially from the shaft into close proximity of a wall of the cylinder. Each impeller may include an arcuate distal end portion farthest from the shaft. The distal end portion of each impeller consists of iridium or an iridium alloy and the remainder of the impeller consists of platinum or a platinum alloy. The stirring apparatuses reduce metal loss from the refractory metal of the stirring apparatus.

Abstract: Stirring apparatuses for stirring molten glass are disclosed. The method includes stirring a molten glass with a stirrer comprising a layer containing at least about 50% iridium. An apparatus comprising an iridium-containing layer is also presented. In one embodiment, an apparatus for stirring molten glass includes a cylinder comprising a bore. A stirrer may be disposed in the bore. The stirrer may include a platinum or platinum alloy shaft coaxial with the cylinder. A plurality of impellers may project radially from the shaft into close proximity of a wall of the cylinder. Each impeller may include an arcuate distal end portion farthest from the shaft. The distal end portion of each impeller consists of iridium or an iridium alloy and the remainder of the impeller consists of platinum or a platinum alloy. The stirring apparatuses reduce metal loss from the refractory metal of the stirring apparatus.

Abstract: Stirring apparatuses for stirring molten glass are disclosed. The method includes stirring a molten glass with a stirrer comprising a layer containing at least about 50% iridium. An apparatus comprising an iridium-containing layer is also presented. In one embodiment, an apparatus for stirring molten glass includes a cylinder comprising a bore. A stirrer may be disposed in the bore. The stirrer may include a platinum or platinum alloy shaft coaxial with the cylinder. A plurality of impellers may project radially from the shaft into close proximity of a wall of the cylinder. Each impeller may include an arcuate distal end portion farthest from the shaft. The distal end portion of each impeller consists of iridium or an iridium alloy and the remainder of the impeller consists of platinum or a platinum alloy. The stirring apparatuses reduce metal loss from the refractory metal of the stirring apparatus.

Abstract: Apparatus and methods for making glass are provided. The apparatus comprise a first glass melt station and a standpipe. The standpipe includes a first end portion in fluid communication with the first glass melt station. The standpipe further includes a gravity trap that is configured to inhibit formed impurities from traveling from at least a portion of the standpipe through the first end portion of the standpipe. The methods comprise the steps of providing the first glass melt station with glass melt, sensing a condition of a quantity of glass melt within the standpipe, and inhibiting formed impurities from traveling from at least a portion of the standpipe through the first end portion of the standpipe.