Dilatometer setup for low coefficient of thermal expansion materials measurements in the 140 K-250 K temperature range

Ruven Spannagel; Ines Hamann; Josep Sanjuan; Thilo Schuldt; Martin Gohlke; Ulrich Johann; Dennis Weise; Claus Braxmaier

doi:10.1063/1.4965813

Dilatometer setup for low coefficient of thermal expansion materials measurements in the 140 K-250 K temperature range

Rev Sci Instrum. 2016 Oct;87(10):103112. doi: 10.1063/1.4965813.

Authors

Ruven Spannagel¹, Ines Hamann¹, Josep Sanjuan², Thilo Schuldt², Martin Gohlke², Ulrich Johann³, Dennis Weise³, Claus Braxmaier¹

Affiliations

¹ University of Bremen, Center of Applied Space Technology and Microgravity (ZARM), 28359 Bremen, Germany.
² German Aerospace Center, Institute of Space Systems, 28359 Bremen, Germany.
³ Airbus Defence and Space, 88039 Friedrichshafen, Germany.

PMID: 27802733
DOI: 10.1063/1.4965813

Abstract

Space applications demand light weight materials with excellent dimensional stability for telescopes, optical benches, optical resonators, etc. Glass-ceramics and composite materials can be tuned to reach very low coefficient of thermal expansion (CTE) at different temperatures. In order to determine such CTEs, very accurate setups are needed. Here we present a dilatometer that is able to measure the CTE of a large variety of materials in the temperature range of 140 K to 250 K. The dilatometer is based on a heterodyne interferometer with nanometer noise levels to measure the expansion of a sample when applying small amplitude controlled temperature signals. In this article, the CTE of a carbon fiber reinforced polymer sample has been determined with an accuracy in the 10^-8 K^-1 range.