摘要:
A method is described for improving resistance to chemical attack by aluminum or magnesium in refractory components. In one method, a slurry is formed comprising-calcium silicate-containing refractory material and a barium-containing compound. This slurry is placed in a mould, then dewatered to form a component which is hydrothermally processed to form a final component. In a second procedure, a silica-containing porous refractory component is impregnated with an aqueous solution of an oxide or hydroxide of barium or strontium and thereafter dried in air.
摘要:
A method is described for improving resistance to chemical attack by aluminum or magnesium in refractory components. In one method, a slurry is formed comprising calcium silicate-containing refractory material and a barium-containing compound. This slurry is placed in a mould, then dewatered to form a component which is hydrothermally processed to form a final component. In a second procedure, a silica-containing porous refractory component is impregnated with an aqueous solution of an oxide or hydroxide of barium or strontium and thereafter dried in air.
摘要:
A method and apparatus for the casting of a composite metal ingot comprising at least two separately formed layers of one or more alloys. An open ended annular mould has a feed end and an exit end and divider wall for dividing the feed end into at least two separate feed chambers, where each feed chamber is adjacent at least one other feed chamber. For each pair of adjacent feed chambers a first alloy stream is fed through one of the pair of feed chambers into the mould and a second alloy stream is fed through another of the feed chambers. A self-supporting surface is generated on the surface of the first alloy stream and the second alloy stream is contacted with the first stream such that the upper surface of the second alloy stream is maintained at a position such that it first contacts the self-supporting surface where the self-supporting surface temperature is between the liquidus and solidus temperatures of the first alloy or it first contacts the self-supporting surface where the self-supporting surface temperature is below the solidus temperatures of the first alloy but the interface between the two alloys is then reheated to between the liquidus and solidus temperatures, whereby the two alloy streams are joined as two layers. The joined alloy layers are then cooled to form a composite ingot. This composite ingot has a substantially continuous metallurgical bond between alloy layers with dispersed particles of one or more intermetallic compositions of the first alloy in a region of the second alloy adjacent the interface. The combination of an alloy of high strength bonded to a surface layer of higher ductility gives a sheet of improved bendability compared to the high strength alloy used alone.
摘要:
A method and apparatus are described for the casting of a composite metal ingot comprising at least two separately formed layers of one or more alloys. An open ended annular mould has a feed end and an exit end and divider wall for dividing the feed end into at least two separate feed chambers, where each feed chamber is adjacent at least one other feed chamber. For each pair of adjacent feed chambers a first alloy stream is fed through one of the pair of feed chambers into the mould and a second alloy stream is fed through another of the feed chambers. A self-supporting surface is generated on the surface of the first alloy stream and the second alloy stream is contacted with the first stream such that the upper surface of the second alloy stream is maintained at a position such that it first contacts the self-supporting surface where the self-supporting surface temperature is between the liquidus and solidus temperatures of the first alloy or it first contacts the self-supporting surface where the self-supporting surface temperature is below the solidus temperatures of the first alloy but the interface between the two alloys is then reheated to between the liquidus and solidus temperatures, whereby the two alloy streams are joined as two layers. The joined alloy layers are then cooled to form a composite ingot. This composite ingot has a substantially continuous metallurgical bond between alloy layers with dispersed particles of one or more intermetallic compositions of the first alloy in a region of the second alloy adjacent the interface.
摘要:
A method of producing a clad sheet article having superplastic properties, and the resulting clad sheet article. The method involves producing a cladding layer onto at least one rolling face of a core ingot made of a metal having superplastic properties, preferably by co-casting, to form a clad ingot and then rolling said clad ingot to produce a sheet article. The core ingot includes an element that diffuses from an interior of the ingot to a surface at superplastic forming temperatures thereby deteriorating surface properties of the ingot. The cladding layer is provided with an element (dopant) that reacts with the element of the core to reduce the ability of the element to diffuse through the cladding layer.
摘要:
A method and apparatus for casting metals in a DC mold to form an ingot or product having at least two layers formed by sequential solidification. The apparatus has at least one cooled divider wall at the entry end portion of the mold to divide the entry end portion into at least two feed chambers. Metal is fed to the chambers to form an inner layer and at least one outer layer. The divider wall has a metal-contacting surface for contacting the metal for the at least one outer layer, the surface being arranged at an angle to the vertical sloping away from the metal for the outer layer in a downward direction. The angle increases at positions on the divider wall spaced from a central section of the wall approaching each longitudinal end thereof. The apparatus is suitable for casting a metal having a high coefficient of contraction as an inner layer or core ingot, e.g. a high-Mg or high-Zn aluminum alloy, or metal combinations having a large difference in their coefficients of contraction.
摘要:
A method of casting a metal ingot with a microstructure that facilitates further working, such as hot and cold rolling. The metal is cast in a direct chill casting mold, or the equivalent, that directs a spray of coolant liquid onto the outer surface of the ingot to achieve rapid cooling. The coolant is removed from the surface at a location where the emerging embryonic ingot is still not completely solid, such that the latent heat of solidification and the sensible heat of the molten core raises the temperature of the adjacent solid shell to a convergence temperature that is above a transition temperature for in-situ homogenization of the metal. A further conventional homogenization step is then not required. The invention also relates to the heat-treatment of such ingots prior to hot working.
摘要:
Devices for cleaning the human tongue and methods for making such devices are disclosed. The tongue cleaner may include a tongue brush and a tongue scraper. The tongue cleaner may be of unitary injection molded construction. The tongue cleaner bristles may be tapered to a point for cleaning crevices of a human tongue, and the bristles may be angled or curved. The tongue scraper contains at least one blade for removal of undesirable material from the tongue by a scraping action. The tongue brush and tongue scraper may be combined into one unit or may be made and used separately.