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:
The present invention relates to the fabrication of low cost, in situ, porous metallic, ceramic and cermet foam structures having improved mechanical properties such as energy absorption and specific stiffness. Methods of fabricating the structures from compositions including ceramic and/or metallic powders are provided. The flowable compositions also include an immiscible phase that results in pores within the final structure. Furthermore, the structures may be shaped to have external porosity, such as with mesh-like structures.
摘要:
This invention relates to rigid porous carbon structures and to methods of making same. The rigid porous structures have a high surface area which are substantially free of micropores. Methods for improving the rigidity of the carbon structures include causing the nanofibers to form bonds or become glued with other nanofibers at the fiber intersections. The bonding can be induced by chemical modification of the surface of the nanofibers to promote bonding, by adding "gluing" agents and/or by pyrolyzing the nanofibers to cause fusion or bonding at the interconnect points.
摘要:
Composites of a matrix of metal fibers and carbon fibers interlocked in and interwoven among a network of fused metal fibers are inherently capable of displaying a broad range of values of a particular physical property. Where the composite is made by sintering a preform of the fiber network dispersed in a matrix of an organic binder, the value of the physical property of the resulting composite is a function of several independent variables which can be controlled during composite fabrication. With particular regard to the capacitance of a stainless steel-carbon fiber electrode, there is described a method of optimizing capacitance during electrode fabrication.
摘要:
Described herein are nanofibers and methods for making nanofibers that have a plurality of pores. The pores have of any suitable size or shape. In some embodiments the pores are "mesopores", having a diameter between 2 and 50 nm. In some embodiments, the pores are "ordered", meaning that they have a substantially uniform shape, a substantially uniform size and/or are distributed substantially uniformly through the nanofiber. Ordering of the pores results in a high surface area and/or high specific surface area. Ordered pores, without limitation, result in a nanofiber that is substantially flexible and/or non-brittle. The nanofibers and methods for making nanofibers may be used, without limitation, in batteries, capacitors, electrodes, solar cells, catalysts, adsorbers, filters, membranes, sensors, fabrics and/or tissue regeneration matrixes.
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:
Die Erfindung betrifft ein Verfahren zur Herstellung von Keramikfasern mit einer Zusammensetzung im Bereich SiC aus einer Polysilan-Polycarbosilan-Copolymer-Lösung enthaltenden Spinnmasse, wobei die Spinnmasse in einem Trockenspinnverfahren durch Spinndüsen extrudiert und durch einen Spinnschacht zu Grünfasern versponnen wird und die Grünfasern anschließend pyrolysiert werden. Erfindungsgemäß enthält die Polysilan-Polycarbosilan-Lösung zwischen 75 Gew.-% und 95 Gew.-%, insbesondere zwischen 80 und 90 Gew.-% an indifferentem Lösungsmittel und besitzen die Spinndüsen einen Kapillardurchmesser zwischen 20 und 70 μm, insbesondere zwischen 30 und 60 μm, insbesondere zwischen 40 und 50 μm.
摘要:
This invention relates to a process for the production of a shaped composite material and the material obtained through that process. In particular it relates to a process for obtaining a disk of composite ceramic material for disc brakes in which the friction coefficient is varied by varying the composition of the surface layer.