INS LLUCH ANGLES

3-D Printing: From Toys to Jet Engines

 

By: Ashley Kindergan

The hype is indeed justified. From its roots as an experimental technology developed in academic labs, 3-D printing has at this point been used to make an amazing array of things – prosthetic limbs, blood vessels, hearing aids, even houses. Sometimes called additive manufacturing because it involves spreading layer upon layer of material to build something up, rather than cutting shapes from a solid block or sheet, the most common use of 3-D printing is the making of prototypes. Architects, designers, engineers, and product developers use 3-D printers to create plastic models in an hour or two instead of waiting weeks or months for an injection molding facility to complete an order. In other words, the majority of the time, it is still used for a one-off job.

So what of the use of 3-D printing on an industrial scale? At this point, the printing of industrial parts accounts for some 30 percent of the $2.2 billion 3-D printing market. And within that, the printing of metal parts accounts for one-third. But both percentages seem likely to grow larger in the future: Unlike in traditional manufacturing, it’s no more expensive to “print” a metal part with an intricate design than it is to “print” a very basic one. The only thing holding back a wholesale migration of such parts into 3-D manufacturing is that currently available machines cannot make the millions of units mass manufacturing requires quickly enough. The good news? Credit Suisse analyst Jonathan Shaffer thinks 3-D technology will close that gap in the next five years. It just needs to get faster.

Thus far, aerospace companies are the most enthusiastic adopters of 3-D printing, representing 30 percent of the metal printing market. Pratt & Whitney, a subsidiary of United Technologies, uses two dozen printed parts in its PurePower turbofan engines, and the company opened an additive manufacturing research center at the University of Connecticut last year. GE already has two research labs devoted to the technology. In January, Elon Musk’s SpaceX launched a rocket that contained a printed oxidizer valve, and NASA is also testing 3-D printed rocket components. 

Additive manufacturing appeals to these firms not only because it opens the door to designing more complex geometric structures than are possible with traditional manufacturing, but also because they can produce parts with fewer components. Consider a metal fan, for example. Instead of making individual blades and attaching them to a central hub, additive manufacturing allows an engineer to simply design a fan that can be printed as a single structure. A GE jet engine fuel nozzle that once had 18 components, for example, now has just one. Another plus? Engineers can design much lighter metal parts than would be possible using any other method, which can mean big savings on fuel costs. “You can take out a ton of weight in structural areas where you simply couldn’t mill internally using traditional manufacturing methods,” says Shaffer. “What if I could create an airplane wing that, instead of being solid throughout, has a weight-saving honeycomb structure inside? That’s the kind of thing that appeals to aerospace companies.”

The use of 3D printing in aerospace production is still relatively limited, as is the scale of the 3D production facilities themselves. GE is spending $50 million to build a facility in Auburn, Ala., where it plans to print approximately 40,000 metal fuel nozzles each year for its LEAP jet engine. As of now, tens of thousands counts as large-scale production. But emerging technology shows a path toward much bigger numbers in just a few years. 

The most popular method of printing metal involves aiming a single laser beam at a layer of metal powder, melting it (Direct Metal Laser Sintering), and repeating layer by layer until the entire object is complete. But new machines that are just coming to market show how this relatively tedious process could soon be much, much faster. The machines have multiple lasers printing multiple components at once, rather than one at a time. Ten lasers, each printing an arc equivalent to one tenth of a circle’s circumference, for example, will build a cylinder much faster than one laser repeatedly traveling the circle’s entire circumference. The software that coordinates production on these new printers needs to improve before the machines can make finished products in mass quantities, but Shaffer says he believes that will happen within five years. And when that happens, 3-D printing will no longer be just a cool, new technology – in fact, it may well prove disruptive to traditional methods of manufacturing. Over the next few years, both the companies that make 3-D printers and those that produce the software that powers them present interesting opportunities.