Computer tomograph for multiscale testing of polymer and hybrid composites

• Subject Area: Production Technology
• Term: Funded in 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 567367290

The subject of the proposal is a multiscale system for high-resolution computed tomography (CT) analysis of polymer and hybrid materials and components made from them. The integrated microfocus X-ray tube will enable measurements in high resolution (up to max. approx. 1 µm voxel resolution), the mesofocus X-ray tube will be used for solid components. The system geometry will enable scans of samples with diameters of up to 500 mm. It will also include a phase contrast module, which can significantly increase the contrast in weakly absorbing samples. The CT system will be used primarily for the following two research areas: (1) Structural investigation of recycled and composite materials CT measurements in high imaging quality are used, for example, for the morphological evaluation and optimization of recyclates that contain various polymer phases and foreign contaminants in the form of blends. In fiber composites, the fiber orientation can be analyzed as a function of the injection molding, tool and material parameters or also fiber displacements during forming. This enables the simulation and optimization of manufacturing processes, material properties and structural-mechanical behaviour. Damage mechanisms and damage progression during long-term stresses or cyclic tests can also be analyzed using non-destructive intermediate tests. (2) Analysis of ageing and degradation processes The CT system applied for will be used to investigate the ageing and degradation processes of both conventional plastics in the use phase and conventional or biodegradable polymer materials in the environment. The three-dimensional material loss over time induced by degradation processes serves as the basis for models that describe the persistence or material degradation and degradation kinetics for various plastics as a function of the significant material, component and environmental parameters. In summary, the CT system applied for will establish a flexible instrument at Leibniz University Hannover that can be used to examine a wide range of samples on a size scale from the mm range up to a sample diameter of approx. 50 cm. The focus is on the investigation of plastics, fiber composites and hybrid materials. At the same time, the system is also designed for the investigation of materials that are difficult to penetrate, e.g. material composites or metallic materials, with regard to internal university co-users. Compared to conventional systems, phase contrast CT significantly increases the information content and enables analyses that would otherwise not be possible due to insufficient differentiation between different components. This will significantly expand the material analysis potential of the applicant and Leibniz Universität Hannover as a whole.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Computertomograph zur multiskalaren Prüfung von Polymer- und Hybridverbundwerkstoffen
• Instrumentation Group: 4070 Spezielle Röntgengeräte für Materialanalyse, Strukturforschung und Werkstoff-Bestrahlung
• Applicant Institution: Gottfried Wilhelm Leibniz Universität Hannover
• Leader: Professor Dr.-Ing. Hans-Josef Endres