Ruby
Ruby - Chromium doped aluminum oxide (Cr:Al2O3)
Physical Properties
- Specific Gravity 3.9 to 4.1
- Hardness 9
- Refractive Index 1.76-1.77
- Fluorescent Lifetime 3.0ms at 300K
- Spectral Linewidth 11cm^-1,5.3A
- Major Pump Bands 404nm and 554nm
- Doping Level .05% by wt.
TECHNICAL DATA PROPERTIES OF SYNTHETIC SAPPHIRE & RUBY
- Chemical Formula: AL 2 0 3 (monocrytalline/hexagonal)
- Density: 0.143 lb/in 3 (3.97 gm/cm 3 )
- Specific Gravity: 3.97
- Tensile Strength: 60,000 psi (2600 kg/cm 2 ) min @ 25°
- Compressive Strength: 350,000 psi (21,000 kg/cm 2 )
- Modulus of Rupture: 67,000-95,000 psi (4000-7000kg/cm 2 )
- Modulus of Rigidity: 25 x 10 6 psi (19,000 kg/mm 2 )
- Young's Modulus: 51 x 10 4 psi
- Hardness: 9 (MOHS) /1800?2200 (KNOOP) / 2500-3000 (VICKERS)
- Poisson's Ratio: 0.28 ? 0.33
- Coefficient of Friction: 0.14 (Dry Friction on Steel)
- Porosity: 0 %
THERMAL
- Melting Point: 3725 0 F (2053 0 C)
- Specific Heat: 0.18 cal/g 0 C
- Thermal Conductivity: 0.09 cal/sec?cm 0 C
- Maximum Operating Temperature: 3632 0 F (2000 0 C)
- Coefficient of Thermal Expansion: 4.8?5.3x10 -6 cm/cm 0 C
ELECTRICAL
- Electrical Resistivity: 10 16 ohm?cm (@25 0 C)
- Dielectric Strength: 480,000 volt/cm (@60 Hz)
- Dielectric Constant: 8.5 ? 10.5 (300 KHz ? 1 GHz)
- Dielectric Loss Tangent: < 0.0001