NOVEL HIGH SPECIFIC STIFFNESS MATERIALS For SPACE APPLICATIONS

Within the European Space Industry newly developed materials are continually being developed with significantly improved levels of specific stiffness.  These are primarily aimed at mass reduction whilst maintaining the performance.  Furthermore, by carefully selecting high specific stiffness materials, it should be possible to better tune the other material properties such as coefficient of thermal expansion (CTE), thermal conductivity or strength toward specific values.

The main objective of the presented study was to select the most promising metallic based composites (MMC) which have a high specific stiffness (> 34 x10⁶ m²/s² ) to be used on planetary spacecraft such as for Mars surface missions.  The selected materials have been tested with respect to the microstructure as well as to the mechanical, corrosion and CTE properties upon earth environment taking into account the materials behavior in different directions.  Based on the findings from the earth test campaign two materials were down selected for the tests under simulated Martian environment such as temperature (-120 /+ 125°C) and pressure of CO2 atmosphere (6mbar).  The results of this study will be presented in this paper.