Quartz glass is made by melting various pure natural quartz (such as crystal, quartz sand, etc.). The coefficient of linear expansion is extremely small, which is 1/10-1/20 of that of ordinary glass, and has good thermal shock resistance. It has high heat resistance, with regular usage temperatures ranging from 1100 ℃ to 1200 ℃, and short-term usage temperatures up to 1400 ℃. Quartz glass is mainly used as Laboratory equipment and refining equipment for special high-purity products. Due to its high spectral transmission, it will not be damaged by radiation (other glass will darken after being exposed to radiation), making it an ideal glass for spacecraft, wind tunnel windows, and spectrophotometer optical systems.
Quartz glass is a special industrial technology glass with a single component of silica. This type of glass has a high hardness of up to seven Mohs, high temperature resistance, low expansion coefficient, heat shock resistance, chemical stability, and good electrical insulation performance. It can also pass through ultraviolet and infrared rays. Except for hydrofluoric acid and hot phosphoric acid, it has good acid resistance to general acids. Divided into two categories based on transparency: transparent and opaque. According to purity, it can be divided into three categories: high-purity, ordinary, and doped. Made from crystal, silica, and silicides, through high-temperature melting or chemical vapor deposition. The melting methods include electric melting, gas melting, etc.
There are two types of quartz glass: transparent and opaque. Transparent and opaque quartz glass are the most economically valuable materials used in industry and scientific research. The raw materials used for its manufacturing (using smelting methods) are crystal or high-purity, ultra-high-purity quartz sand (transparent quartz glass) and white quartz sand (opaque quartz glass). Both of these raw materials exist in nature and are composed of the purest SiO2.
Quartz glass and crystal have the same Chemical composition, but they are quite different in structure. One is in a glass state, and the other is in a crystalline state. Crystals cannot withstand high temperature Thermal shock. When it encounters high temperature, it will break and transform into other crystals. Quartz glass can withstand extremely high temperature shock. The production of transparent and opaque quartz glass requires high temperatures, as crystalline SiO2 can only melt at temperatures above 1713 ℃.
Performance of quartz glass
Quartz glass is known as the "glass king" because it has a series of special physical and chemical properties.
The Chemical composition of quartz glass is a single component of SiO2, which is usually called purity.
Illuminated quartz glass
Quartz glass for semiconductor industry
Thermal properties of quartz glass
Temperature resistance
thermal stability
Volatility of quartz glass at high temperatures
Specific heat and thermal conductivity
Crystallization performance (also known as crystallization performance or devitrification performance) of quartz glass
High temperature discoloration of quartz glass
The above quartz glass performance is transparent quartz glass, other varieties of quartz glass (opal quartz glass, quartz ceramics, opaque quartz glass, quartz wool, quartz fiber, etc.)