| 摘要 |
In order to provide a quartz glass crucible distinguished by high purity, high opacity and/or low transmissibility in the IR spectrum, it is proposed on the basis of a known quartz glass crucible of opaque quartz glass with a crucible body symmetrical in relation to a rotational axis, an outer zone (3) of opaque quartz glass transitioning radially toward the inside into an inner zone (2) of transparent quartz glass and with a density of at least 2.15 g/cm3, that according to the invention, the crucible body (1) be made of a synthetic SiO2 granulate with a specific BET surface ranging from 0.5 m2/g to 40 m2/g, a tamped volume of at least 0.8 g/cm3 and produced from at least partially porous agglomerates of SiO2 primary particles. A process for producing a quartz glass crucible of this kind is distinguished according to the invention in that for the production of the crucible a SiO2 granulate is used which was formed from at least partially porous agglomerates of synthetically manufactured SiO2 primary particles and that it has a specific BET surface ranging from 0.5 m2/g to 40 m2/g and a tamped volume of at least 0.8 g/cm3, the heating effected in such a way that a vitrification front advances from the inside outward while an inner zone (4) of transparent quartz glass is being formed.
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