Sapphire glass generally refers to synthetic sapphire, which is very different from the jewels that people usually understand - natural sapphire. It is generally used in the manufacture of watch mirrors.
Sapphire is a generic name for corundum gemstones in addition to red rubies in corundum gemstones. The main component is alumina (Al2O3). Sapphire glass is a synthetic sapphire that can easily and inexpensively produce gem-quality sapphire in the laboratory with the same chemical composition and physical properties as natural sapphire.
Sapphire glass is similar to the corundum component, the hardness is 9, and various kinds of chemical elements can be added to produce various colors. Nowadays, colorless is commonly used. Its advantages are higher than ordinary glass, and the price is relatively high, mainly used to make the watch of high-end watches.
Sapphire glass and ruby glass has excellent thermal properties, excellent electrical and dielectric properties, and chemical corrosion resistance. It is resistant to high temperatures, good heat conductivity, high hardness, transparent infrared, and good chemical stability. Therefore, it is commonly used to replace other optical materials to make optical components, transparent infrared optical windows, and is widely used in infrared and far-infrared military equipment, such as: for night vision infrared and far infrared sights, night vision cameras and other instruments. And instruments for satellite and space technology, as well as windows for high-power lasers, various optical prisms, optical windows, UV and IR windows and lenses, observation ports for low-temperature experiments, and high-precision instruments for marine aerospace.
+ Property of Sapphire Glass:
1) Crystal structure: hexagonal crystal system
2) Cell parameters: a=4.785Å , c=12.991Å
3) Melting point: 2045℃
4) Density: 3.98g/cm3
5) Mohs hardness: 9
6) The coefficient of thermal expansion: 5.8×10 -6 /K
7) Specific heat: 0.418W.s/g/k
8) Thermal conductivity: 25.12W/m/k (@ 100℃)
9) Refractive index: no =1.768 ne =1.760
10) Dn/dt: 13x10 -6 /K(@633nm)
11) Light transmittance: T≈80% (0.3～5μm)
12) Dielectric constant: 11.5(∥c), 9.3(⊥c)