Heraeus Quarzglas Gmbh & Co Kg

Rolf G&ouml;bel

Waltraud Werdecker

Heinz Fabian

Johann Leist

Bruno Uebbing

Udo Gertig

Erich Rosin

Based on a known process for the manufacture of opaque quartz glass, by mixing SiO particles and an additive which is volatile at a melting temperature, forming a body and melting said body with an advancing melt front forming in the body, it is proposed according to the invention that in order to reduce the danger of contamination, a body ( ) be formed with an inner bore ( ) and be heated in such a manner that the melt front ( ) advances from the inner bore ( ) to the outside. The article of pure opaque quartz glass according to the invention has high resistance to temperature change, high mechanical strength and good chemical durability. It is distinguished by an opening ( ) enclosed by an inner wall ( ), with an inner SiO surface layer ( ) having a layer thickness ranging from 30 mm to 500 mm and a density of at least 2.15 g/cm .

Process for making opaque quartz glass and opaque component made according to the process

In a known process for the production of opaque quartz glass a blank is formed from synthetic SiO granulate and is heated at a vitrification temperature to form a body of opaque quartz glass. In order to provide on this basis a process for the production of pure opaque quartz glass with a homogenous pore distribution, high density, high viscosity and a low tendency to devitrify, it is proposed according to the invention that the SiO granulate to be used is a SiO granulate ( ) composed of at least partially porous agglomerates of SiO primary particles, with a specific BET surface ranging from 1.5 m /g to 40 m /g and an apparent density of at least 0.8 g/cm . A SiO granulate ( ) suitable for the implementation of the process is distinguished in that it is formed from at least partially porous agglomerates of SiO primary particles and in that it has a specific BET surface ranging from 1.5 m /g to 40 m /g and an apparent density of at least 0.6 g/cm .

Process for making opaque quartz, for carrying out the process suitable SiO2 granulate, and component of opaque quartz glass

Growing community of inventors

Gelnhausen, Germany

Rolf Göbel

Growing community of inventors

Gelnhausen, Germany

Rolf G&ouml;bel

Rolf Göbel