Laboratories for Materials Testing at Cryogenic Temperatures
Since 2022, the Faserinstitut Bremen e.V. has been investigating the suitability of materials at cryogenic temperatures. The rationale behind this research is that carbon-fiber-reinforced plastic (CFRP), with its outstanding mechanical properties, is fundamentally well-suited for pressure tanks as well as for tanks used to store cryogenic liquid hydrogen. The behavior of metallic materials, welds, and adhesives, as well as monitoring systems, under cryogenic temperatures is also of great interest for the development of tanks and tank systems and is the subject of research and development at FIBRE.
The institute’s work focuses on analyzing the effects of superimposed static and dynamic loads, both mechanical and thermal. A key research objective is to gain a sound understanding of initial damage and damage progression. This knowledge is then used to improve the material, e.g., through optimized reinforcing textiles, laminate structure, and new or modified polymer matrices.
| 100 kN LN2 Testing Machines: Static and Dynamic | Tensile Test with LN2 |
To this end, the Faserinstitut Bremen e.V. operates state-of-the-art tensile testing machines (static and dynamic) in the cryogenic laboratory at the ECOMAT Research Center, which operate in liquid nitrogen at nearly -200°C. These machines will be supplemented in January 2025 by a dynamic tensile testing machine, whose temperature-controlled specimen chamber is cooled to 15 K using cryogenic helium and which will be equipped with a helium permeability measurement system. The aim is to investigate the relationship between loads and damage progression in the form of microcracks and increasing helium permeability.
The ECOMAT facility also houses a TMA for determining the CTE between 5 K and 200°C, a rheometer for temperatures down to -160°C, and a helium-operated permeation measurement system for pressures up to 100 bar.
Currently, the Faserinstitut Bremen e.V. is collaborating with the DLR Institute of Space Systems (DLR-RY) on the installation of additional tensile testing machines that will operate with liquid hydrogen. The machines are scheduled to be commissioned by the end of 2025, following an extensive renovation of the hydrogen laboratory on the DLR premises.
