Sapphire Filament

Sapphire Filament exhibits outstanding thermal resistance, mechanical strength, and corrosion resistance, particularly under extreme environments. It serves critical roles in optoelectronics, magnetometry, and high-temperature fiber applications. Sapphire filament is used in LED production, magnetic susceptibility balances, and as optical carriers in harsh environments where traditional fibers degrade. Notably, filaments fabricated via edge-defined film-fed growth (EFG) exhibit low transmission loss and withstand high-temperature and chemically reactive media, making them ideal for sensing or light-guiding in aerospace, nuclear, and molten metal systems. In instrumentation, sapphire filaments provide superior mechanical linearity and longevity over quartz or metal wires. This format is central to precision and durability demands in advanced instrumentation and next-gen light-emitting platforms.

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Tolerance

Properties

Reference & Citations

each

Tolerances

Filament

Diameter		±20%
Length		+5% / -1%

Material Properties for Ceramics

Chemical Resistance

Element	Value
Acids - concentrated	Good
Acids - dilute	Good
Alkalis	Good
Halogens	Good
Metals	Good

Electrical Properties

Element	Value
Dielectric constant	7.5-11.5
Dielectric strength( kV mm⁻¹ )	15-50
Volume resistivity( Ohmcm )	>10¹⁴@25

Physical Properties

Element	Value
Refractive index	1.71-1.79
Useful optical transmission range	200-5500nm
Apparent porosity( % )	0
Water absorption - saturation( % )	0
Density( gcm⁻³ )	3.985

Thermal Properties

Element	Value
Melting point( C )	2050
Upper continuous use temperature( C )	1800-1950
Specific heat( J K⁻¹ kg⁻¹ )	750@25°C
Thermal conductivity( W m⁻¹ K⁻¹ )	35-40@20°C
Coefficient of thermal expansion( x10⁻⁶ K⁻¹ )	5.8@20-1000°C