Glass Ceramic Zerodur — Thermal Expansion

Zerodur is a glass ceramic produced by Schott Glas in Mainz, Germany. It is designed for zero thermal expansion around room temperature. This material is often used for high performance terrestrial telescopes. The figure shows the linear thermal expansion between -150°C and 100°C. The sample was measured twice at a heating rate of 3 K/min in a helium atmosphere. The measured CTEs between 0°C and 50°C are in excellent agreement with the literature values (Schott brochures). (measurement with DIL 402 C)