synthetic sapphire
synthetic sapphire
synthetic sapphire
synthetic sapphire
synthetic sapphire

Welcome to sapphire world!

Synthetic sapphire is transparent single crystal 99.99% pure Al2O3 that exhibits a unique combination of physical, chemical, electrical and optical properties: high thermal conductivity, high strength and scratch resistance, hardness (9 on the Mohs scale), transparent in wide range of wavelength, chemical inertness.
High crystal perfection, low reactivity, and appropriate unit cell size make sapphire an excellent substrate in the semiconductor industry for blue light-emitting diodes (LED).
Since Nobel Laureate in Physics Shuji Nakamura used the sapphire substrate in 1990s for LED, the demand of sapphire crystal has been growing rapidly.

It drives development of new markets like general lighting, backside lighting in TV-sets, displays, consumer appliances, aerospace and defense, and other applications

Properties of sapphire

Chemical formula Al2O3
Density 3.97 g/cm3
Hardness 9 Mohs
Melting point 2050oC
Max. use temperature 1800-1900oC
Tensile strength 250-400 MPa
Compressive strength 2000 MPa
Poisson's ratio 0.25-0.30
Young's Modulus 350-400 GPa
Bending strength 450-860 MPa
Rapture Modulus 350-690 MPa
Linear expansion rate (at 293-323 K) 5.0*10-6K-1(⊥ C)
6.6*10-6K-1(∥ C)
Thermal conductivity (at 298 K) 30.3 W/(m*K)(⊥ C)
32.5 W/(m*K)(∥ C)
Specific heat (at 298 K) 0.10 cal*g-1
Resistivity (at 298 K) 5.0*1018 Ω*cm(⊥ C)
1.3-2.9*1019 Ω*cm(∥ C)
Dielectric constant (at 298 K, in 103-109 Hz interval) 9.3 (⊥ C)
11.5 (∥ C)