Zerodur

Applications

1. Optics
2. Microlithography
3. Measurement technology

   Properties

• Particularly low thermal expansion: in the range 0 to 50 °C it has a mean of 0 ± 0.007 K⁻¹, which is two orders of magnitude better than that of fused quartz.
• High 3D homogeneity with few inclusions, bubbles and internal stria.
• Hardness similar to borosilicate glass, so that it can be ground and polished more easily than fused quartz.
• High affinity for coatings.
• Low helium permeability.
• Non-porous.
• Good chemical stability similar to that of fused quartz.
• Fracture toughness approximately 0.9 MPa·m^1/2.

  Physical properties

• Dispersion: = 0.00967
• Density: 2.53 g/cm³ at 25 °C
• Young's Modulus: 9.1 Pa
• Poisson Ratio: 0.24
• Specific heat capacity at 25 °C: 0.196 cal/ = 0.82 J/
• Coefficient of thermal expansion : 0.05 ± 0.10/K
• Thermal conductivity: at 20 °C: 1.46 W/
• Maximum application temperature: 600 °C
• Impact resistance behavior is substantially similar to other glass