Nov 7 2002
Background
This is synthetically produced Sapphire. Single Crystal Sapphire has a high thermal conductivity, volume resistivity, hardness and wear resistance, as well as a high upper use temperature.
The energy band gap is large (10eV). Single Crystal Sapphire is a transparent material having useful transmission of wavelengths in the range 0.2 to 5.5 microns.
It is much stronger than glass and can be used as viewing windows in high pressure and vacuum applications.
Key Properties
The key properties of Single Crystal Sapphire are tabulated below.
Table 1. Key properties
| Physical Properties |
| Apparent Porosity |
0% |
| Density |
3.985 g.cm-3 |
| Refractive Index |
1.71-1.79 |
| Useful Optical Transmission Range |
200-5500 nm |
| Water Absorption – Saturation |
0% |
| Electrical Properties |
| Dielectric Constant |
7.5-11.5 |
| Dielectric Strength |
15-50 kV.mm-1 |
| Volume Resistivity at 25 °C |
>1014 ohm.cm |
| Thermal Properties |
| Melting Point |
2050 °C |
| Specific Heat at 25 °C |
750 J.K-1.kg-1 |
| Thermal Conductivity at 20 °C |
35-40 W.m-1.K-1 |
| Thermal Expansion, 20-1000 °C |
5.8x10-6 K-1 |
| Upper Continuous Use Temperature |
1800-1950 °C |
| Mechanical Properties |
| Compressive Strength |
2100 MPa |
| Hardness – Knoop |
2000 kgf.mm-2 |
| Hardness – Vickers |
1600-1800 kgf.mm-2 |
| Tensile Modulus |
350-390 GPa |
| Chemical Resistance |
| Acids – Concentrated |
Good |
| Acids – Dilute |
Good |
| Alkalis |
Good |
| Halogens |
Good |
| Metals |
Good |
About Goodfellow
Goodfellow supplies metals, ceramics and other materials to meet the research, development and specialist production requirements of science and industry worldwide.
.gif)
*Note: All data provided on this page have been supplied by the distributor. AZoM.com take no responsibility for the accuracy of this data and recommend you contact the supplier before applying it.
Source: Goodfellow
For more information on this source please visit Goodfellow.