Yttrium-Aluminum Garnet (YAG) is isotropic crystal with cubic symmetry. It has excellent optical and thermodynamic properties. Its mechanical properties and chemical stability are close to those of sapphire crystals without the birefringence effect of sapphire. Pure YAG crystals have higher transmittance in the 0.25~5um region, and no absorption at 2-3μm , while glass has strong H2O absorption band. Therefore, undoped pure YAG crystal is a new type of substrate and window material for ultraviolet and infrared optical equipment. At the same time, the excellent physical and chemical properties and optical properties of YAG crystal make it an important optical application in high-temperature and high-energy physical environments.
Physical-Chemical Properties
| Structure | Cubic |
| Lattice Constant | 12.01Å |
| Melting Point | 1970℃ |
| Hardness (Mho) | 8.5 |
| Density | 4.55±0.04g/cm3 |
| Specific Heat | 0.59J/g•cm-3@0-20℃ |
| Elastic Modulus | 310GPa |
| Youngs Modulus | 3.17x104kg/mm2 |
| Poisson Ratio | 0.3 |
| Tensile Strength | 0.13-0.26GPa |
| Thermal Expansion Coefficient | [111]: 7.8x10-6/℃@0-250℃ [110]: 7.7x10-6/℃@0-250℃ [100]: 8.2x10-6/℃@0-250℃ |
| Thermal Conductivity | 14W/m/K@20℃ 10.5W/m/K@100℃ |
| Thermo-Optic Coefficient | dn/dt = 7.3x10-6/℃ |
| Thermal-Shock Resistance | 800W/m |
| Solubility | Insoluble in water and slightly soluble in acid |
PRODUCT DATA SHEET OF OPTOELECTRONICS MATERIALS
Technical Index
| Crystal Orientation | [111] or [100], Offset 5° within |
| Size | Custom-made size upon request |
| Wavefront Distortion | ≤0.125l/25mm |
| Dimensional Tolerance | Diameter: 0.05mm; Thickness: 0.1mm |
| Cylindrical Processing | Fine grinding or polishing |
| Parallelism of End Face | ≤20 |
| Flatness of End Face | l/10 |
| Surface Quality | 10-5(MIL-O-13830A) |
| Inverted | 0.15±0.05mm |
| Anti-reflection coating reflectivity | ≤0.2%@Special wavelength |
Optical Properties
| Refractive Index | 1.8197@1064mm |
| Transmission Range | T>80% @250-5000nm |
| Anti-light Damage Threshold | ≥15Jcm-2@1064nm |
