Engineers at Trinity College Dublin are leading an international study to develop a new technology for 3D printing metal components, reports the Irish Times.
The $757,000 four-year project represents the largest single research award made to the university by the European Space Agency (ESA).
According to an excerpt from Trinity College, the new technique will help the space agency acquire unique engineering components with previously unavailable characteristics. On the other hand, the researchers say, the same 3D method could also be used to make the ultimate non-stick frying pan and components for the family car.
The goal is to improve efficiency and reduce the cost of a manufacturing process called “cold spray”, effectively a new kind of three dimensional printing. The difference with conventional 3D printing, however, is that the components are metal and engineered to a very high standard, reports the Irish Times.
“This is the largest ESA research project awarded to Trinity, and we will bring cold spray to the next level,” says Prof Rocco Lupoi who leads the project. “We want to make cold spray cheaper without losing performance,” says Lupoi who is assistant professor in mechanical and manufacturing engineering at Trinity.
Some of the technical problems to be overcome include delivering a fast process that remains highly precise and reducing the current high cost of cold spray manufacture. “It is a challenging project but there is a detailed technical plan approved by ESA that will address all of these issues in a four-year period,” Lupoi opined.
3D printing is nothing new, making an object by applying layer after layer of material to achieve a final shape. However, current technology mainly works with plastic.
Cold spray printing is different: it can make finely engineered metal parts while working at room temperature. Bonding does not rely on heat, and it needs no special environment to allow bonding to take place. Low temperatures are useful in a metallic environment because there is no heat-related distortion or damage to the components.
There are other advantages for cold spray, Lupoi says. It is not polluting and it doesn’t require toxic materials to make it work, relying only on pure non-toxic helium.
Less raw material is needed with cold spray technology making it “less wasteful and more environmentally friendly,” he argues. The general term for it is “additive manufacturing” he says, an approach ranked as a top 10 breakthrough technology by MIT’s technology review.
“Engineering components usually start with a large piece of metal and this is reduced to the size and shape you need,” says Lupoi. “Cold spray works like a painting machine, applying layer after layer to build up a shape, but done in a matter of seconds.”
The key to this technology according to the research team is speeding up the sprayed material to supersonic speeds, twice the speed of sound in fact or 2,472km per hour. Helium gas is used as a carrier of the metallic particles that you want to apply. “You accelerate the gases to supersonic velocity and if you inject particles into the gas they will also reach supersonic speeds,” Lupoi explains.
“The particles are moving fast enough to penetrate into the surface and bond in a quick way so you can build up say five millimeters of material in a mater of seconds, 1,000 times faster than other techniques.”
As reported by the Irish Times/ Image credits: Brenda Fitzsimons