Evaluation of Nanocomposites as Lightweight Electronic Enclosures for Satellites\u27 Applications

The United States military is exploring the use of nanocomposite materials for satellite structural applications. Current composite spacecraft structures are nonconductive and must have expensive shielding materials applied in order to protect the spacecraft from catastrophic damage that can be caused by electromagnetic interference (EMI) and/or electrostatic discharge (ESD) which are characteristics of the space environment. Conductive nanocomposites are being developed for spacecraft structures that will provide ESD and EMI shielding protection without the need for expensive secondary shielding materials. This thesis studied one such material consisting of M55J/RS-3 composite combined with nickel nanostrands™. Four different configurations were tested for their ultimate tensile strength (UTS) and EMI shielding properties before and after exposure to the space environment. The four configurations tested were a baseline panel consisting of M55J/RS-3 and three configurations with different layers of nickel nanostrands™ added to the control specimen: exterior, interlaminar, and mid-plane. These four were further tested for their EMI and resistivity properties before, during and after monotonic tension tests of increasing loads up to fracture. This study found that the UTS and Young’s modulus (E) do not change after exposure to the space environment, EMI shielding of the exterior specimen is 25% better than the control specimen, sheet resistance measurements show that exterior specimens are 11% better at ESD protection than the control, and failure mechanisms are the same regardless of composite configuration: The 90° plies failed first, causing delamination in the 0/90 plies leading to transverse matrix cracking and delamination in the ±45 plies resulting in ultimate failure, and in all configurations the nanostrand layers were not damaged