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Published on: April 27, 2016
Summary
Large Zerodur optics exhibit a delayed elastic effect under low stress, causing reversible strain over weeks. This time-dependent behavior is crucial for optical design applications.
Area of Science:
- Materials Science
- Optical Engineering
- Physics
Background:
- Zerodur is a glass-ceramic material widely used in large optics due to its low thermal expansion.
- Understanding material behavior under stress is critical for the performance and longevity of optical systems.
Purpose of the Study:
- To investigate the mechanical behavior of large Zerodur optics under prolonged low-stress conditions.
- To characterize the delayed elastic effect in Zerodur at room temperature.
Main Methods:
- Continuous mechanical testing of large Zerodur optics at room temperature.
- Utilizing a high-performance mechanical profilometer to measure strain.
- Monitoring strain during both load application and recovery phases.
Main Results:
- A significant delayed elastic effect was observed in Zerodur under low stress levels.
- A reversible strain of approximately 1% was measured over several weeks.
- The observed phenomenon is time-dependent, elastic, and reversible.
Conclusions:
- Zerodur exhibits time-dependent elastic behavior (delayed strain) under low stress at room temperature.
- This elastic effect, though reversible, must be considered in the design of optical systems using Zerodur.
- Accurate optical design requires accounting for this delayed strain phenomenon over time.
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