Page 109 - International Space Station Benefits for Humanity, 3rd edition.

Materials

The International Space Station (ISS) provides a unique laboratory environment for the testing of new
materials. Sedimentation and buoyancy-driven convection do not take place in microgravity, thus
allowing us to witness how materials change and develop over longer periods. This allows researchers
to manipulate their materials in unique ways. These opportunities are leading to a better understanding
of how material processes work on Earth, thereby enabling the manufacturing of new materials with
well-defined structures, improved strength and better function.

Improved Industrial Casting Models
and Casting Processes
The world is facing many ecological and economic The main goal of this research
challenges, The European Space Agency’s (ESA’s) is to increase understanding of
materials science research is addressing these material solidification processes
challenges as part of a world-class program involving
hundreds of international partners from academia and in order to develop new, stronger,
industry. The main goal of this research is to increase lightweight materials that will have
understanding of material solidification processes in
order to develop new, stronger, lightweight materials a significant impact on industry.
that will have a significant impact on industry.
Another important goal of the research is to help
resolve some of the most pressing issues facing
the planet, such as improving fuel efficiency, and CETSOL has been studying the microstructure of
improving the consumption and recycling of materials. aluminum alloy samples formed during solidification,
Columnar-to-Equiaxed Transition in Solidification specifically focusing on how columnar dendritic
Processing (CETSOL) is one of the many materials or tree-like structures in a solidifying melt evolve
projects supported by ESA on the ISS. It was the into randomly oriented “branches,” the ‘equiaxed’
first experiment to start processing in the Materials structure, and the parameters that influence this
Science Laboratory on the ISS at the end of 2009. transition. The determination of the internal (micro)

A typical microstructure obtained in a CETSOL sample containing a grain refiner. The sample was
directionally solidified in the ISS Materials Science Laboratory.
Image credit: CETSOL science team

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