Last year NASA emailed a wrench to the International Space Station. The file was then downloaded and 3D printed.
It showed the huge potential that 3D printing can have for space applications. But there remains the problem that 3D printing is an incredibly slow process; it can take hours to create objects of any significance.
However, researchers in Ireland are now re-working a process invented during the 1980s that could create a new 3D printer and at the same time vastly speed up the printing process.
Cold spray is a coating technique that involves firing particles at a surface to build up a physical object.
“At the end of the four years we will have a fully functional, I would call it a new 3D printer – it might not be called cold spray then – which will be able to make 3D shapes with a number of metals,” said Dr. Rocco Lupoi, who is leading the research at Trinity College Dublin.
“The usual ways at the moment are not through accelerating materials, they are on a layer-by-layer process.”
He said that building layers on top of each other can be a time consuming process, but as cold spray is accelerating particles it allows 3D shapes to be created quickly.
Any new technique that is created could be used in space and for space applications, as the research is being funded by the European Space Agency (ESA).
It may also be used back on Earth. “You could have a very open area where you have a robot arm holding a cold spray nozzle which is going to do certain operations on perhaps aircraft components or automotive components,” he said.
“It’s a coating technology,” he said. “It’s possible to create coatings or add other materials on top of other material in a solid state.”
He said it is based upon accelerating small particles up to supersonic velocities that are “well above the speed of sound”. When the particles hit a surface they bond to it and to themselves, enabling layers to be created.
“The build rate of this process is 1,000 times more than other processes in the 3D printing area.”
“We would like to make things in 3D. We want to make metal components because space is predominantly metals.”
However one of the biggest challenges of the project will be to try and reduce the cost of cold spray technology, as it is one of the biggest inhibitors that is preventing it from growing at present.
“It uses large amounts of helium and helium is an expensive resource. We’re going to try and drive down the costs,” Lupoi said.
However one of the biggest advantages, other than the speed, is that the technique can be used to create layers of different metals, something that traditional 3D printing techniques are currently unable to process.
In total the researchers have received a €500,000 grant from the ESA to complete the four year project.