Silicate glass refers to glass whose basic component is SiO2. It has many varieties and is widely used. According to different content of SiO2 and alkali metal and alkaline earth metal oxide in glass, it is divided into:
1.Quartz glass. SiO2 content is more than 99.5%, thermal expansion coefficient is low, high temperature resistance, good chemical stability, transparent UV light and infrared light, high melting temperature, high viscosity, and molding are difficult. Used in semiconductors, electric light sources, light guide communications, lasers, and other optical and optical instruments.
2.High silica glass. Also known as vycor glass, the main component is SiO2 content of about 95% to 98%, containing a small amount of B2O3 and Na2O, its nature and quartz glass similar.
3.Soda-lime glass. With SiO2 content as the main component, it also contains 15% Na2O and 16% CaO. Its cost is low, it is easy to be shaped, it is suitable for large-scale production, and its output accounts for 90% of the utility glass. Can produce glass jars, flat glass, utensils, light bulbs and so on.
4.Lead silicate glass. The main components are SiO2 and PbO, which have unique high refractive index and high volume resistance, and have good wettability with metals. They can be used to manufacture light bulbs, vacuum tube columns, crystal glass vessels, and Flint optical glass. Lead glass containing a large amount of PbO can block X-rays and gamma rays.
5. Aluminosilicate glass. With SiO2 and Al2O3 as the main components, the softening deformation temperature is high. It is used in making discharge bulbs, high-temperature glass thermometers, chemical combustion tubes, and glass fibers.
6. Borosilicate glass. With SiO2 and B2O3 as the main components, it has good heat resistance and chemical stability and is used to make cooking utensils, laboratory instruments, metal welding glass and so on.Borosilicate glass is mainly composed of B2O3 and has a low melting temperature to resist sodium vapor corrosion. The rare earth borate glass has a high refractive index and low dispersion, and is a new type of optical glass. Phosphate glass with P2O5 as the main component, low refractive index, low dispersion, used in optical instruments.