3Tehran, Tarbiat Modarres University, Faculty of Electrical Engineering, Department of Engineering, PO Box 111-14115
4Tehran, Tarbiat Modarres University MSc in Polymer Engineering, Department of Chemical Engineering, Department of Polymer Engineering, PO Box 111-14115
5Tehran, MSc Electrical Engineering Contacts Tarbiat Modarres University, Faculty of Electrical Engineering, Department of Engineering, PO Box 111-14115
In this research, microcellular thermoplastic polyurethane foams are investigated as an absorbing material in the X-band (8.2-12.4GHz) frequency range by means of numerical analysis and experiment. In the frame of this work, we aim at establishing relationships between the foams morphology including cell size and air volume fraction and their radar absorbing properties. We therefore first describe numerical method and modelling. Then numerical analysis of microcellular foams in various cell sizes and air volume fractions are explained. Then design basis and preparation of nanocomposite foams of various morphologies using supercritical carbon dioxide (scCO2) as physical foaming agent are presented. After measuring the S-Parameters of the samples by VNA, numerical and experimental results are compared and finally we establish structure/properties relationships that are essential for further optimizations of the materials for the radar absorbing applications.