摘要:
The invention relates to a method for producing a silica glass article, involving method steps i.) providing a silica granulate made of a pyrogenically produced silica powder, ii.) forming a glass melt from the silica granulate, iii.) forming a silica glass article from at least some of the glass melt, iv.) comminuting the silica glass article so as to obtain silica glass grains, v.) processing the silica glass article to obtain a preform, and vi.) forming an opaque silica glass article from the preform. The invention further relates to an opaque silica glass article that can be obtained by said method. The invention also relates to a reactor and an arrangement, each of which can be obtained by further processing the opaque silica glass article.
摘要:
A porous cellular body comprising primarily a porous sintered glass material is disclosed. The porous sintered glass material primarily includes a first phase and a second phase, the first phase primarily comprising amorphous fused silica and the second phase comprising amorphous fused silica and a sintering aid.
摘要:
In a known composite material with a fused silica matrix there are regions of silicon-containing phase embedded. In order to provide a composite material which is suitable for producing components for use in high-temperature processes for heat treatment even when exacting requirements are imposed on impermeability to gas and on purity, it is proposed in accordance with the invention that the composite material be impervious to gas, have a closed porosity of less than 0.5% and a specific density of at least 2.19 g/cm3, and at a temperature of 1000° C. have a spectral emissivity of at least 0.7 for wavelengths between 2 and 8 μm.
摘要:
A porous cellular body comprising primarily a porous sintered glass material is disclosed. The porous sintered glass material primarily includes a first phase and a second phase, the first phase primarily comprising amorphous fused silica and the second phase comprising amorphous fused silica and a sintering aid.
摘要:
Apparatus for sintering a hollow cylindrical body (1) of porous synthetic silica comprises a hollow mandrel (2) for supporting the body in a horizontal position. The mandrel is housed within a vacuum furnace (5) having heating elements (4) arranged to surround the body circumferentially along its entire length. A method of sintering a hollow cylindrical body (1) of porous synthetic silica is also disclosed.
摘要:
Methods for the production of opaque quartz glass are known, according to which a suspension containing amorphous SiO2 particles is produced, a porous green body is formed therefrom, the green body is dried and then condensed by sintering during the formation of opaque quartz glass. In order to expand on this method and allow a reproducible production of opaque quartz glass which is minimally susceptible to cracks, using the slurry method, and to produce a green body (semifinished product) which is distinguished by a minimal susceptibility to cracks, it is suggested according to the invention to form a green body from a SiO2 matrix and quartz glass filaments embedded therein. The green body obtained from the method is characterized in that quartz glass filaments are embedded in a matrix produced by casting and drying a suspension containing amorphous SiO2 particles.
摘要:
Methods for the production of opaque quartz glass are known, according to which a suspension containing amorphous SiO2 particles is produced, a porous green body is formed therefrom, the green body is dried and then condensed by sintering during the formation of opaque quartz glass. In order to expand on this method and allow a reproducible production of opaque quartz glass which is minimally susceptible to cracks, using the slurry method, and to produce a green body (semifinished product) which is distinguished by a minimal susceptibility to cracks, it is suggested according to the invention to form a green body from a SiO2 matrix and quartz glass filaments embedded therein. The green body obtained from the method is characterized in that quartz glass filaments are embedded in a matrix produced by casting and drying a suspension containing amorphous SiO2 particles.
摘要:
A known SiO2 slurry for the production of quartz glass contains a dispersion liquid and amorphous SiO2 particles with particle sizes to a maximum of 500µm, wherein the largest volume fraction is composed of SiO2 particles with particle sizes in the range 1µm - 60µm, as well as SiO2 nanoparticles with particle sizes less than 100nm in the range 0.2 - 15% volume by weight (of the entire solids content). In order to prepare such a slurry for use, and to optimize the flow behavior of such a slurry with regard to later processing by dressing or pouring the slurry mass, and with regard to later drying and sintering without cracks, the invention suggests a slurry with SiO2 particles with a multimodal distribution of particle sizes, with a first maximum of the sizes distribution in the range 1µm - 3µm and a second maximum in the range 5µm - 50µm, and a solids content (percentage by weight of the SiO2 particles and the SiO2 nanoparticles together) in the range 83% - 90%.