Preparation method of quartz glass

Abstract

The invention discloses a preparation method of quartz glass. The method comprises the steps of: (a) heating quartz particles to partial melting to form a porous quartz body; (b) subjecting the porous quartz body obtained in step (a) to dehydration treatment so as to obtain a dehydrated porous quartz body; and (c) heating and sintering the porous quartz body obtained in step (b) to form the quartz glass. The invention relates to the technical field of preparation of a quartz glass material from quartz sand or quartz powder through oxyhydrogen flame, as a breakthrough, quartz sand at a semi-molten state is sprayed to the porous quartz body, and the porous quartz body is dehydrated, the hydroxy content is greatly reduced to less than 15ppm, or even below 5ppm, thus improving the purity of the prepared quartz glass material without significant increase of the preparation cost by a simple preparation process and preparing the high purity quartz glass.

Description

technical field [0001] The invention belongs to the field of optical fibers and cables, and more particularly, relates to a preparation method of quartz glass. Background technique [0002] Quartz glass is widely used in light source, electronics, optical communication, instrumentation, laser, aerospace, nuclear technology and national defense due to its excellent high temperature resistance, thermal expansion coefficient, thermal shock resistance, chemical stability, insulation and optical properties and other high-tech fields. At present, the mainstream production methods of high-purity quartz glass are chemical synthesis method, electrofusion method, gas refining method and plasma spraying. [0003] Chemical synthesis is carried out using silicon-containing precursors such as SiCl 4 etc.), heated by flame, reacted with hydrogen and oxygen, hydrolyzed to form silica soot body, deposited on the target target to form porous quartz body, and then dehydrated and sintered at ...

AI Technical Summary

Problems solved by technology

The electrofusion method is to place the quartz sand in a high-temperature-resistant container and heat it through an electric furnace to directly melt the quartz sand to form quartz glass. The purity and uniformity of the quartz glass prepared by this method are not high, and bubbles are easily generated inside. It is generally used for Preparation of quartz products with lower requirements; plasma spraying technology is to melt and spray quartz sand on the target target through a plasma flame to directly form transparent quartz glass. This technology has been used in some enterprises to prepare high-purity quartz columns and quartz tubes. However, due to the limitation of high equipment cost, high energy consumption and long production cycle, it has not been widely used; the gas refining method is currently the most widely used preparation technology in the quartz product industry. The quartz sand is heated by a hydrogen-oxygen flame and fused and deposited On the target target, quartz glass is directly formed by heating the flame. The content of bubbles and defects in the quartz glass prepared in the early stage of this method is relatively high. With the development of technology, the prepared quartz glass has been improved in size and performance. Improvement, the patent CN105314825A mentioned that adding low-pressure acetylene to the flame can improve the uniformity of the quartz interior; the patent JP6122131A replaced the hydrogen-oxygen flame with CO and O 2 , thereby reducing the content of hydroxyl groups in the quartz glass, but due to CO and O 2 The heat of combustion is only 1 / 3 of the hydrogen-oxygen flame, which prolongs the production cycle and introduces the toxic gas CO

Although the production cost of gas refining equipment is low and it is easy to realize large-scale production, the produced quartz glass generally has a high hydroxyl content (above 150ppm), bubbles exist inside, and the stress distribution is uneven

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