Microstructure Analysis and Determination of Material Characteristics of PU Foams with Varying Densities

Abstract

An algorithmic material characterisation and selection based on digital tools provide numerous possibilities to implement innovative leight-weight solutions into future projects. Cellular materials offer tremendous potential with regard to weight reduction of load-bearing structural components. Therefore a profound understanding of the materials composition and its influence on the global mechanical properties is necessary. In the following thesis polyurethane foams are characterised regarding their microstructural composition and global mechanical properties to identify and evaluate microstructural parameters influencing the foams behaviour. In order to so, several mechanical test series are conducted including varying test parameters such as foam density, sample positioning, orientation, and loading type. Additionally digital microstructural analyses of samples from different positions are going to depict the microstructural foam composition. The results prove the influence of the foams density on its properties. This can be seen in the microstructure and the mechanical tests. The influence of the sample positioning couldn’t be proved based on the collected data, however, the mechanical results clearly depict the effects of the sample orientation on the global foam properties. The derived correlations show the influence of the microstructure on the foams macroscopic behaviour. In order to use the results as a learning foundation for digital systems further examinations have to be conducted.