摘要:
An extrusion method and apparatus are described for producing ceramics, glass, glass-ceramics, or composites suitable for use as proppants. The method includes forming one or more green body materials, extruding the green body materials to form a green body extrudate, separating and shaping the green body extrudate into individual green bodies, and sintering the green bodies to form proppants. The apparatus includes a means for forming an intimate mixture of green body materials, means to produce a green body extrudate, means for separating and shaping the green body extrudate into individual green bodies, and means to sinter the green green bodies to form proppants.
摘要:
An electrode can include a functional layer having an Ln2MO4 phase, where Ln is at least one lanthanide optionally doped with a metal and M is at least one 3d transition metal, and a heavily-doped ceria phase. An electrochemical device or a sensor device can include the electrode.
摘要:
A low surface friction body for a drill bit includes a matrix drill bit body. The body includes a particulate phase having a friction-reducing additive, and a binding material that bonds the particulate phase using a suitable manufacturing process such as selective laser sintering. The particulate phase may include tungsten carbide, the friction-reducing additive may be polytetrafluoroethylene, and the binder material may be copper or cobalt. The friction-reducing additive is distributed throughout at least a portion of the drill bit body that includes the surface that will come into contact with drill cuttings and drilling fluid during operation. The molecular properties of the friction-reducing additive result in a drill bit body having a surface that is resistant to sticking even after enduring chipping and other types of wear.
摘要:
A castable refractory composition may include from 5% to 95% by weight of alumina, aluminosilicate, or mixtures thereof; up to 70% by weight silicon carbide; up to 10% by weight carbon; from 0.1% to 5% by weight alkaline earth metal oxide and/or hydroxide; and from 0.1% to 5% by weight of silica having a surface area of at least about 10 m2/g. The refractory composition may further include no more than 0.5% by weight of cementitious binder, and the refractory composition may not release a significant amount of hydrogen gas upon addition of water. The refractory composition may set on addition of water. An installable refractory lining may be formed using the composition and a method including at least one of casting, self-flowing, wet shotcreeting, rodding, cast-vibrating, spraying, conventional dry gunning, or high density gunning the castable refractory composition, and setting and drying the composition.
摘要:
A method of manufacturing a ceramic primary crown including mixing a source material including zirconia or alumina that configures a frame of a primary crown, a polymer for reducing viscosity and applying ductility upon injection molding, and a toner for providing the same or similar color as baby teeth, heating the polymer contained in the mixed source material to have ductility, injection molding the heated source material, extracting the polymer to reduce brittleness and increase ductility with respect to the injection-molded matter, removing fat to completely eliminate the polymer element from the injection-molded matter, from which the polymer is partially extracted through the polymer extraction, sintering the fat-removed body, from which the polymer is removed, to improve mechanical properties, and polishing an outer surface of the sintered body to provide gloss, and performing barrel-finishing to remove a burr.
摘要:
The present invention relates to a molded ferrite sheet having opposing surfaces and a thickness in a range of 30 μm to 430 μm, at least one surface of said opposing surfaces having the following surface roughness characteristics (a) to (c): (a) a center line average roughness is in a range of 170 nm to 800 nm, (b) a maximum height is in a range of 3 μm to 10 μm, and (c) an area occupancy rate of cross-sectional area taken along a horizontal plane at a depth of 50% of the maximum height in a square of side 100 μm is in a range of 10 to 80%.
摘要:
The present invention relates to a novel process for producing ceramic materials, in particular refractory materials having a reduced relative density. In particular, the invention relates to a process for producing light, refractory materials having non-contiguous pores based on shaped and unshaped materials. These materials can be used as working lining in high-temperature applications. The process is based on the production of spherical, closed and isolated pores in the microstructure of the material. The pores having a pore diameter which can be set in a targeted manner are generated by use of polymer particles, in particular polymethacrylates, in particular polymers or copolymers prepared by means of suspension polymerization, as pore formers which can be burnt out. The polymers or copolymers are present in the form of small spheres having a defined diameter. The introduction of isolated spherical pores allows the production of ceramic materials having a sometimes significantly reduced relative density and improved corrosion resistance and better mechanical strength compared to the prior art. The specific, closed pore system at the same time contributes to reducing the thermal conductivity of the ceramic materials. In addition, the novel process has the advantage that there is no risk of formation of undesirable black cores, even in the production of thick-walled ceramic products.
摘要:
An extrusion method and apparatus are described for producing ceramics, glass, glass-ceramics, or composites suitable for use as proppants. The method includes forming one or more green body materials, extruding the green body materials to form a green body extrudate, separating and shaping the green body extrudate into individual green bodies, and sintering the green bodies to form proppants. The apparatus includes a means for forming an intimate mixture of green body materials, means to produce a green body extrudate, means for separating and shaping the green body extrudate into individual green bodies, and means to sinter the green green bodies to form proppants.
摘要:
There is provided a method for the fabrication of porous SiC ceramic. The method comprises oxidizing particles of SiC ceramic thereby forming amorphous silica on the surface of the particles. The oxidized SiC particles are then mixed with an additive. Alternatively, layer(s) of the additive is (are) deposited on their surface by sol-gel technique. The oxidized SiC particles mixed or coated with the additive are then mixed with at least one pore-former. Alternatively, the oxidized SiC particles mixed or coated with the additive are coated with layer(s) of a polymer or pore-former by in-situ polymerization. In embodiments where the oxidized SiC particles are mixed with an additive and a pore-former or polymer, a further additive may be used. In each of these embodiments, the resulting product is then compacted into a green body which is heated and sintered to yield the porous SiC ceramic material. There is also provided a porous SiC ceramic fabricated by the method according to the invention.