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Novel materials or multilayers can help to reduce the mass requirement for radiation shielding of electronic components significantly. In this paper, potential alternatives to the standard aluminum shielding approach are assessed by the Monte-Carlo simulations and promising candidates are manufactured and characterized by radiation tests including proton and electron tests. The transmission of energetic protons of up to 39 MeV through the shielding solution was assessed as well as the dose deposited by energetic electrons up to 12 MeV in Radiation sensing field-effect transistor (RADFETs) and Alanine dosimeters behind the shield.

This work presents the use of carbon nanotube (CNT) skeletons and the resin infusion process as a path towards the production of polymer composites with high and well dispersed nanotube content. A general purpose low viscosity epoxy resin was used as matrix in the reported process assessment. Thin CNT papers, called skeletons, were initially produced to obtain CNT networks. The impregnation was made by infiltrating the non-diluted resin through the carbon nanotube structure. The results show the proposed processing approach as one capable of producing well dispersed nanocomposites with high CNT loading (more than 15 wt% CNT by composite weight), which are important for developing high performance structures based on carbon nanotubes with good thermal and electrical conductivity. The absolute mechanical performance was lower than expected, and discussed in light of manufacturing problems detected by microscopy observations under scanning electron microscopy (SEM).

Metal matrix composites with embedded multiwall-carbon nanotubes (MWNT) are attractive because MWNTs exhibit high intrinsic thermal conductivity. Thus to improve the thermal conductivity of a metal matrix, silver matrix composites with MWNT were prepared by “chemical” mixing, different active elements were introduced enhancing the bonding between inclusions and matrix. The evolution of the thermal conductivity and the coefficient of thermal expansion CTE as a function of the MWNT concentration and the presence of active elements cobalt, molybdenum or nickel in the silver matrix in Ag–X/MWNT composites are presented. A transition from weak to strong matrix/MWNT bonding is observed by adding active elements, the latter leading concomitantly to an increase in thermal conductivity and a decrease in CTE. The thermal conductivity was found to increase by up to 10% for a composition of 0.2 wt.% MWNT and cobalt as active element and a 6% decrease in CTE compared to a pure silver reference.

A baseline electroless deposition processes for Cu on CNTs has been developed. This process results in the formation of copper particles of few tens of nanometres. Using this process in a CNT loaded solution it is possible to obtain a homogeneous distribution of CNTs and Cu, even for volume fraction of CNTs as high as 17 v%. By the application of wet chemical processing it is possible to penetrate the natural felt-like structure of the CNTs and to fill the gaps with copper particles. Variations of the baseline deposition process have been established, allowing adding small amount of nickel on the CNT prior to the copper deposition to strengthen the interfacial bonding between matrix and CNTs. Hot pressing of the highly CNT loaded metal matrix composites has been developed; it allows producing bulk material that can be handled. The microstructure of these materials has been investigated and samples have been machined for further testing, i.e. mechanical characterization and thermo-physical properties.

At the Fachgebiet Raumfahrttechnik of the Technical University at Munich, electrothermal and electromagnetic launchers are used to accelerate projectiles to velocities of 5–15 km s−1 to simulate the impact of micrometeorites on structure of spacecraft. The discharge of stored electrical energy (in the order of some kJ) across selected materials generates a plasma armature, which accelerates the projectile. Without a projectile a high pressure (in the order of 10–50 kbar) plasma pulse (duration 10–50 μs, temperature approximately 1–104 K, 106–107 W cm−2) is accelerated to velocities of up to 20 km s−2. This pulse, to which selected materials (e.g., Cr, C) can be deliberately added, is directed towards the surface of a target for treatment. Experiments with steel targets show that an extremely hard surface layeer of average 30 μm thickness is created by a single pulse [1]. The surface layer thickness could be increased to approximately 400 μm by repetitive impacting. After 10 process steps, where the target is placed with a small offset after each “shot”, an adhesive surface layer with a fairly high surface roughness is produced. The surface layer has then to be ground to a thickness of 200 μm in a subsequent step to achieve a smooth surface. The surface layers are investigated by means of metallography, scanning electron microscopy (SEM) and X-ray diffraction. The layer consists of two different zones with a measured microhardness up to 1300 HV0.01. There is a very hard white etching zone immediately below the surface, and a dark etching zone between the white zone and the core workpiece which has a needle-shaped martensitic microstructure. Preliminary results indicate that the white zone, which is created after every new impact, transforms into the dark zone in dependence on temperature during subsequent treatments. The production of very hard adhesive surface layers with thicknesses of minimum 200 μm is a further step towards industrial application of this method.

This work provides information on the characterization of carbon nanotube (CNT) skeletons, or Buckypapers, using contact angle and thermogravimetric analysis (TGA) measurements. The preparation of composites using these CNT skeletons and an epoxy resin by impregnation in vacuum and cure in two moulds with different release surfaces is described. Preliminary results for the mechanical performance of the produced composites using mini-tensile test specimens and their characterization by TGA, dynamic mechanical thermal analysis (DMTA) and scanning electron microscopy (SEM) is also presented., This study was performed in the frame of the project "Non-Conventional Matrix/CNT Reinforced Composites", Contract 20521/06/NL/SFe 19128 funded by ESA, the European Space Agency. The authors would like to acknowledge Prof. Maria C. Paiva for helping with the SEM analyses.