Outstanding advantages of synthetic sapphire and ruby
» High polish and low friction » Hardness » Miniature size, close tolerances » Long, accurate wear life » Resistance to heat, corrosion and deformability » Non-magnetic properties » High dielectric strength
2050° C
5,4-106/0 C face perp. C axis
6,2-106/0 C face parall. C axis
Mechanical properties
Hardness mohs
Hardness knoop
Modulus of elasticity
9
1800 face perp. C axis
2200 face parall. C axis
4,4 x 106 kg/cm2/±1% young
Chemical properties
Acids and alkalis attack
Porosity
0 at 300° C
0
Electrical properties
Dielectric constant
Electrical resistence
9,4 at 11,3
1011 ohm/cm at 500°
106 ohm/cm at 1000°
103 ohm/cm at 2000°
Optical properties
Refractive index (at 5893 A nd)
Cromatic dispersion (6563)
Transmission visible
Infrared (th.1mm)
Ultraviolet:
Standard corundum
UV corundum
1760 face perp. C axis
1769 face parall. C axis
0,011
Excellent, 85%, 0.75-5 µ
50%, 6 µ
80% 4000 – 3000 A
50% 2000 A
80% 4000 – 3000 A
75% 2000 A
65% 1800 A
50% 1600 A
30% 1470 A