Properties and characteristics of quartz glass

The optical properties of quartz glass are unique. It not only transmits far ultraviolet spectra, but also visible light and near-infrared spectra, surpassing all ultraviolet transmission materials. Users can select the required variety from the 185-3500 m band as needed. Because quartz glass has high temperature resistance, a very small coefficient of thermal expansion, good chemical and thermal stability, and its bubbles, streaks, homogeneity, and birefringence are comparable to ordinary optical glass, it is an important optical material with high stability in various harsh environments for optical systems.

　　Quartz glass is a special industrial technical glass made of silicon dioxide, and it is a very good base material. Quartz glass plates have a series of excellent physical and chemical properties, such as:

　　1. High temperature resistance. The softening point temperature of quartz glass is about 1730, and it can be used for a long time at 1100, and the temperature can reach 1450 for a short time.

　　2. Corrosion resistance. Except for hydrofluoric acid, quartz glass hardly reacts with other acids. Its acid resistance is 30 times that of ceramics and 150 times that of stainless steel. In particular, its chemical stability at high temperatures is unmatched by any other engineering material.

　　3. Good thermal stability. The thermal expansion coefficient of adaptive glass is very small, and it can withstand drastic temperature changes. If quartz glass is heated to around 1100, it will not burst even if placed in normal temperature water.

　　4. Good light transmittance. Quartz glass plates have excellent light transmission performance in the entire spectral band from ultraviolet to infrared, with visible light transmittance above 93%, especially in the ultraviolet spectral region, the transmittance can reach more than 80%.

　　5. Good electrical insulation performance. The electrical resistance value of quartz glass is 10,000 times that of ordinary glass. It is an excellent electrical insulating material, and it has good electrical properties even at room temperature.

　　Quartz glass fiber, as a high-tech product with excellent electrical insulation, temperature resistance, and mechanical properties, is widely used in aerospace, military, semiconductor, high-temperature heat insulation, and high-temperature filtration fields. This section details the performance, uses, and domestic and international development of quartz glass fiber. Currently, China should vigorously develop the production technology and product types of quartz glass fiber to promote the development of China's aerospace, military, and semiconductor industries.

　　Quartz glass fiber refers to a special type of glass fiber with a high silicon dioxide content and a diameter of 1-15 μm. It has high heat resistance and can be used for a long time below 1050, and its instantaneous high-temperature resistance can reach 1700, second only to carbon fiber. At the same time, due to its excellent electrical insulation, its dielectric constant and dielectric loss factor are the best among all mineral fibers. Therefore, quartz glass fiber is widely used in aerospace and aviation industries.

　　The softening temperature of quartz glass fiber is 1700. Ordinary quartz glass fiber can be used for a long time at 600-1050. When the temperature is higher than 1600, the quartz glass fiber begins to sublime, which is an endothermic reaction that consumes heat energy. With this property, quartz glass fiber can be used as an ablation material for spacecraft and intercontinental missiles returning to the atmosphere. In addition, at high temperatures, quartz glass fiber does not shrink like high-silica fiber. After baking at 1000 for 1000 hours, the loss of quartz glass fiber does not exceed 1.5%.