Sapphire is a crystalline form of aluminum oxide (Al2O3) and is extremely unreactive and chemically-resistant to acids and alkalis, including hydrofluoric acid. Furthermore, sapphire is exceptionally hard with a Moh’s hardness of 9, (compared to diamond = 10 and glass ~5.5). These substrates are therefor very scratch-resistant. Last but not least it can withstand high temperatures, has high thermal conductivity, does not degrade under UV light, and features a high dielectric strength.
These characteristics, and many more, make sapphire a preferred premium material for many applications in photonics, solid-state lighting, scientific research, lenses and covers, design lighting, optical sensors, and many, many more where the environmental conditions are demanding.
Our sapphire substrates come in both clear and frosted versions. If you are in need of different dimensions or thicknesses, or if you have a high volume demand. Please contact us for a quote.
Sapphire material properties:
Property | Items | Unit | Sapphire |
---|---|---|---|
Physical / Optical | Color | - | Transparent |
Material | high purity Al2O3 | ||
Water absorption | % | 0 | |
Optical Transmission @ wavelength | - | >80% @ 310 tot 3000 nm | |
Electrical | Dielectric Constant (1 Mhz) | e | 11.5 parallel to C-axis 9.3-9.5 perpendicular to C-axis |
Dielectric strength | MV/m or KV/mm | ~40 | |
Mechanical | Density | g/cm3 | 3.95-4 |
Flexural Strength (Bending) | Mpa | 350-395 | |
Young’s Modulus | Gpa | 345 | |
Poissons ratio | 0.25-0.30 | ||
Hardness | Moh's scale | 9 | |
Thermal | Coefficient of Thermal Expansion (CTE) | ppm/°C | 6-8 |
Thermal Conductivity (25°C) | W/m‧K | 24~25 |