A comprehensive comparison of Clearceram and Zerodur

Both materials are highly stable, low thermal expansion glass-ceramic materials. Due to their excellent mechanical properties, they are frequently used in high-tech industries, such as astronomical telescope lenses, space exploration structural components, high-precision instruments, etc., which are equipment that is sensitive to temperature changes.

Basic Concepts of Low Expansion Glass

What is low expansion glass?

Low thermal expansion means that the material changes little when subjected to temperature fluctuations. This property will have strong resistance to thermal shock, which is the main cause of material cracking in practical applications. The following are some common glass materials with low thermal expansion:

Key Features Comparison

Clearceram vs Zerodur

Color contrast

Yellow sheen of Zerodur vs. clear appearance of Clearceram
Compared to Zerodur, the clear appearance of Clearceram has high transparency and is more conducive to optically clear applications

Example Case Study

Telescope Mirror Testing
- Source: Study published on PubMed (Dimensional Stability Tests)
- Methodology: Mirrors fabricated from Zerodur and Clearceram-Z were subjected to thermal cycling (-40°C to +90°C) to measure stability.
- Results:
  - Clearceram-Z: Deformation remained within ±0.1 μm/m°C.
  - Zerodur: Deviations reached ±0.2 μm/m°C.
- Conclusion: Clearceram-Z proved superior for high-precision optical systems requiring extreme thermal stability.
Chemical Resistance Test
- Source: OHARA and Schott comparative studies on acid immersion tests.
- Findings:
  - Both materials resisted surface erosion after 24 hours in a 10% hydrochloric acid solution.
  - Surface roughness variations were negligible (<0.01 μm).
Mechanical Durability in Aerospace Applications
- Reference: Technical analysis from Schott AG.
- Outcome: Zerodur’s higher flexural strength was advantageous in aerospace mirrors subjected to high mechanical stresses.

Typical application scenarios for Clearceram and Zerodur

Procurement and machining advice

Choosing the right manufacturer is particularly important. We have extensive experience in Zerodur processing and are committed to providing high-quality precision ceramic components that meet or exceed customer expectations. If you have engineering needs, please feel free to contact our experts. We are happy to provide you with service.

Frequently Asked Questions

Which material, Clearceram-Z or Zerodur, is better suited for aerospace applications?

Zerodur is generally better suited for aerospace applications due to its proven track record in space-based systems like the Hubble Space Telescope. Its superior mechanical strength and dimensional stability under extreme conditions make it ideal for high-stress environments, such as during launch or in orbit.
Clearceram-Z, while excellent for precision optical systems, is more commonly used in applications where ultra-low thermal expansion and optical clarity are prioritized over mechanical robustness.

Why is Zerodur more expensive than Clearceram-Z?

Material Composition and Manufacturing: Zerodur’s production involves complex processes to achieve its exceptional mechanical and thermal properties, especially for large-scale optics.
Proven Space-Grade Performance: Its certification and widespread use in space applications often add a premium to its cost.
Market Demand: Zerodur is often used in unique and large-scale projects, such as telescope mirrors, where the demand for high volumes or large pieces increases costs.
Clearceram-Z, by comparison, is often used in smaller-scale or less mechanically demanding applications, which can reduce overall expenses.

Are there alternative glass-ceramic materials that can replace Clearceram-Z or Zerodur?

ULE® (Ultra-Low Expansion Glass): Produced by Corning, ULE is a high-performance material with extremely low thermal expansion, often used in telescope mirrors and semiconductor equipment.
Astrositall: A cost-effective alternative for dimensional stability applications, commonly used in precision optics and mirrors.
Cordierite: While not a direct substitute, cordierite offers excellent thermal and dimensional stability, particularly for structural or industrial applications requiring lower costs.
BOROFLOAT® and SUPREMAX®: These borosilicate glasses can be used in applications where cost and chemical durability are more critical than thermal stability.