Korth Kristalle GmbH

Refractive Index


Sapphire (Al2O3)

Properties (Al2O3)   
Transmission Range   0,16 - 4,7 µm  
Refractive Index   no=1,766/ne=1,758 @633nm 
Reflective Loss   16,94% @2,9 µm (1 surface)  
Reststrahlen  13.5 µm 
Density   3.99 g/cm3  
Melting Point   2053 °C  
Molecular Weight   101.9613  
Thermal_Conductivity   || C: 35,1perp. C 33 @300K  
Specific Heat   753 J/(kg·K)   
Thermal Expansion   perp. C 5 || C 5,6 · 10-6/ K @293K 
Hardness (Mohs)   || C: 1900 perp. C 2200 
Young`s Modulus   400 GPa
Shear Modulus   145 GPa  
Bulk Modulus   207 GPa  
Rupture Modulus   1200 MPa  
Elastic Coefficient   [C11= 495; C12=160; C33= 497; C44= 146; C13= 115; C14= 23 GPa
Dielectric Constant   || C 10,55; perp. C8,6 
Solubility in Water   unsoluble  
Type of Material   Single crystal, synthetic  
Crystal Structure  hexagonal, a = 4,785 Å  c = 12,991 Å  
Cleavage Planes   no cleavage  
Standard diameter   max. 210 mm  
Application   IR optics, laser optics, pressure optics  
Remarks  resistant against solvents, most acids and bases 

Transmission spectrum


Transmission spectrum-2

Al2O3 englisch

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