2 research outputs found
Additively manufactured mirrors for CubeSats
Additive manufacturing (AM; 3D printing) is a fabrication process that builds an object layer-upon-layer and
promotes the use of structures that would not be possible via subtractive machining. Prototype AM metal mirrors
are increasingly being studied in order to exploit the advantage of the broad AM design-space to develop intricate
lightweight structures that are more optimised for function than traditional open-back mirror lightweighting.
This paper describes a UK Space Agency funded project to design and manufacture a series of lightweighted
AM mirrors to fit within a 3 U CubeSat chassis. Five AM mirrors of identical design will be presented: two in
aluminium (AlSi10Mg), two in nickel phosphorous (NiP) coated AlSi10Mg, and one in titanium (Ti64). For each
material mirror pair, one is hand-polished (including the Ti64) and the other is diamond turned. Metrology
data, surface form error and surface roughness, will be presented to compare and contrast the different materials
and post-processing methods. To assess the presence of porosity, a frequent concern for AM materials, X-ray
computed tomography measurements will be presented to highlight the location and density of pores within the
mirror substrate; methods to mitigate the distribution of pores near the optical surface will be described. As a
metric for success, the AlSi10Mg + NiP and AlSi10Mg mirrors should be suitable in terms of metrology data for
visible and infrared applications respectively