Development and testing of a novel Graphene Based Thermal Strap

A novel graphene based thermal strap was developed within an ESA project with the aim of investigating the possibility of replacing current baseline solution relying on heat pipes for cooling scientific instrumentation onboard the Athena satellite. The strap underwent extensive testing to verify that the thermal, mechanical and cleanliness requirements were fulfilled, achieving TRL-5. The most critical requirements were related to thermal conductance and particulate contamination, for which novel in-house test methods were developed to increase confidence in the test results. The strap was shown to exhibit extraordinary performance with a thermal conductance value of $1.68 \pm 0.05 \mathrm{~W} / \mathrm{K}$ at 173 K, which was well above the ESA requirement of $1 \mathrm{~W} / \mathrm{K}$ and exceeded the best commercial solution by more than $40 \%$. Encapsulation of the graphene strap was proven to effectively inhibit particle release. As a next step, the aim is to commercialize the (patented) thermal strap technology with an industrial partner.