Planetary dust has 3D-printing potential

EXTRATERRESTRIAL inks produced from lunar and Martian dust simulants have been tested to explore 3D-printing’s potential to aid planetary colonisation.

Researchers at Northwestern University, US, have demonstrated that they can make a range of highly elastic structures from little more than dust, which in turn could be used to make buildings in areas with limited resources.

The novel inks used for 3D printing were created by combining NASA-approved dust simulants, an elastomeric binder and a solvent mixture. The dust was sieved and mixed with polylactic-co-glycolic acid copolymer (PLGA), a biodegradable elastomer, before being dissolved in dichloromethane (DCM), 2-butoxyethanol (2-Bu) and dibutyl phthalate (DBP). The resulting inks, approximately 90% dust by weight, could then be stored for up to six months before printing using an extrusion process.

The research, partially supported by funding from Google, was performed by Ramille Shah’s Tissue Engineering and Additive Manufacturing (TEAM) Laboratory at Northwestern's Simpson Querrey Institute for BioNanotechnology. The researchers have previously used a similar process they term “3D painting” to print hyperelastic biomaterials similar to bone, 3D graphene and carbon nanotubes, alongside metals and alloys.

Shah said: 'For places like other planets and moons, where resources are limited, people would need to use what is available on that planet in order to live. Our 3D paints really open up the ability to print different functional or structural objects to make habitats beyond Earth.'

It is believed that this is the first example of rubber-like or soft materials resulting from lunar or Martian simulant materials. By varying printer nozzle size and extrusion pressures, a range of printing resolutions and deposition rates were demonstrated without altering the ink. The resulting 3D-printed material was flexible, elastic and tough, meaning that it can be cut, rolled, folded, and otherwise shaped immediately following printing. There is also the potential for ink components to be reclaimed and recycled.

Shah added 'We even 3D-printed interlocking bricks, similar to LEGO, which can be used as building blocks.'

There are plans to optimise ways to fire these 3D-painted structures in a furnace. This could provide an optional process to transform the soft, rubbery objects into hard, ceramic-like structures for wider application where elasticity and mechanical flexibility is not required.

Nature Scientific Reports http://doi.org/f9wt93