How 3D printing is revolutionizing manufacturing
When you think of 3D printing, you may picture a small desktop machine that turns out little plastic figurines or models of the Eiffel Tower. However, 3D printing has more recently become of great interest to the manufacturing community—and it is well on its way to becoming a major player.
The difference between traditional manufacturing and 3D printing can be seen as a matter of choosing between subtraction or addition. Rather than taking large pieces of solids—plastic, wood, metal, or whatever—and carving pieces out of them, 3D printing uses lasers or electron beams to melt down powdered substances and put down the melted material layer by succeeding layer until the shape is finished. As a result, while the term "3D printing" is still used for the creation of prototypes, the process of creating end products using the technology is now known in industry as additive manufacturing, or AM for short.
According to Terry Wohlers, principal of Wohlers Associates, a consulting firm that specializes in 3D and additive manufacturing, one way you can judge the increase in interest is by the number of companies now selling industrial-grade 3D printers—machines selling for $5,000 or more. According to the Wohlers Report 2018, an estimated 1,768 metal AM systems were sold in 2017, compared with 983 systems in 2016, an increase of nearly 80 percent. Wohlers adds, "In 2016, 97 companies sold machines. Just a year later, 135 companies worldwide sold industrial-grade machines. So we're seeing a lot of growth in the number of system manufacturers." He also pointed to an increase in materials suppliers and in investments in additive manufacturing from major corporations.
What is driving this increased interest in 3D printing?
One part to rule them all
For years, 3D printing technology was considered a "not ready for prime time" technology. It was something consumers might enjoy playing with, and it was good enough for creating prototypes. But the perception was that 3D printing wasn't up to the challenge of serious manufacturing.
Timothy Simpson is the Paul Morrow Professor in Engineering Design and Manufacturing at Penn State University and co-director of the Center for Innovative Materials Processing Through Direct Digital Deposition, or CIMP-3D. According to Simpson, the attitude toward 3D printing in manufacturing changed in 2012, when GE bought a company called Morris Technology, which specialized in additive manufacturing. Using that company's 3D technology, GE engineers created the LEAP fuel nozzle, a part required for its new jet engine. The nozzle had been designed as 20 assembled pieces and could now be created as a single unit.
"They applied similar thinking to what they called the advanced turboprop engine," says Simpson. "It was a smaller aircraft engine for a Cessna. They consolidated something like 855 parts into about 12 components."
With that, the floodgates opened. Manufacturers began looking at 3D printing as a serious possibility to enhance or replace traditional manufacturing practices.
"As a design aid to help with modeling and prototyping, [3D printing is] very important, but it might only be 5 percent of the entire budget of a manufacturing program," explains Wohlers. "Additive manufacturing is now being used for real production. That's where the money is and where companies are taking it. Consolidating many parts into one part is a very important reason why companies might consider using the technology."
A change in outlook
But using additive manufacturing doesn't just take a change in equipment and suppliers. It also means a change in a company's entire outlook on the manufacturing process.
"From a traditional standpoint, if we are machining, casting, or forging a part using the sort of processes that have been around for centuries," says Simpson, "we pick material that we want, we know what its properties are, and then we use the manufacturing process to create the shape that we want. With additive manufacturing, we're flipping that around. We're creating the shape that we want. Depending on how you create that shape, you may get different properties afterwards."
Irene Petrick is director of industrial innovation at Intel and co-author with Simpson of a 2013 paper titled "3D Printing Disrupts Manufacturing." She says, "We train our design engineers in mechanical and electrical physics-based work. Those designers have been trained to take a block of something and subtract metal or other materials from it to create a part. Because of that, they're very limited to what's possible to make in terms of shapes."
However, such limitations don't apply to parts created using 3D printing. "For example, you could never produce a nautilus shell in a subtractive manufacturing world, but you can in an additive world," Petrick says. "We're seeing some of those honeycombs and nautilus shells and other kinds of nature-inspired shapes coming into play because they have much higher strength-to-weight ratio. Many experienced designers are really challenged with how to take advantage of a new way of design, given that 3D manufacturing allows things that weren't possible before."
Simpson adds, "[3D printers] don't care whether you're making an intricate lattice structure or a solid material. I can make any shape that I want, and I even have the ability to control the microstructure and hence the material properties. To be able to have that level of control has been very expensive, very time consuming, or in some cases, impossible to do."
In fact, a wide range of products are now being made using 3D printers—and they are not limited to parts for the aerospace industry. "Several hundred thousand metal hip cups for hip replacements have already been produced with 3D printing," says Pete Basiliere, research vice president at Gartner and co-author of "Hype Cycle for 3D Printing." "People don't realize that they have a 3D printed piece in their hip." Other products that need a high-level of customization, such as hearing aids, are also being manufactured using 3D printers, he adds.
Still to be solved
There are still hurdles to be jumped. AM technology is still much slower than traditional manufacturing. And once you've created your part, you still have to make sure it is up to standard.
"In traditional [manufacturing]," says Simpson, "I design [the product] and I give the drawings or blueprints to a manufacturing engineer to think about how it's going to be made. There's a human in the loop who says, 'Hey, you know, why did you design it this way? It's going to be too expensive!' or 'I can't make that with this machine!' The computer doesn't care. It's going to take whatever you've designed, slice it up, and then send that to the machine, and there's no human in the loop anymore to catch your errors."
But that has its advantages as well. Basiliere points out that traditionally designed products pass through a gauntlet of compromises demanded by a company's engineers, accountants, and management before it even reaches the prototype stage. "What 3D printing does is enable us to manufacture the ideal design because we're building one layer on top of another," he says. "We can produce the part that the customer really wants, not some kind of lowest common denominator compromise."
And, of course, there's the matter of formal quality control. "A big problem with using 3D printing is when you have a distributed production system," says Petrick. "How do you assess liability? Who is ultimately responsible? We don't know how that's going to turn out from a case law perspective, but I suspect that a blockchain or something similar will become the technology of record for how that part was produced and how quality was built into it."
"The systems are improving, but many still are not up to manufacturing quality standards," explains Wohlers. "If you look at conventional machine tools such as CNC milling machines and injection molding machines and a host of others, customers expect a certain level of quality. The additive manufacturing industry is making significant improvements, but it's still not where it needs to be in terms of production repeatability and reliability. It's one thing to produce a prototype, but it's an order of magnitude more difficult to produce an entire process that meets manufacturing standards. That's something that will change and improve in the coming years."
3D on its way
Additive manufacturing has a way to go yet. While the cost of the printers has come down as more and better models become available, they are still a considerable investment.
But that doesn't mean they can't be a good investment, even—or especially—for a small company looking to introduce a new product. "If you're a start-up company and you have a product idea, you can get a product out there without going through a lot of upfront capital expenditures like tooling," says Wohlers. "You can put out a few products and see if there's a market appetite, and if there's enough, you can go the conventional route, which can drive down the cost."
He adds, "You know, we're seeing a lot of products that would have never seen the light of day, but now they are being introduced because it's affordable to do so."
"Where 3D printing really shines is when we create a design that can only be made with 3D printing," says Basiliere. "The use cases are starting to really grow as engineers learn how to design for 3D printing and have confidence in the performance characteristics of 3D output. I refer to it as moving from a design for manufacturing to manufacturing the ideal design."
Wohlers adds, "We have a lot of work yet to do. Don't always believe what you read. Some articles will lead you to believe that they're already printing hearts and kidneys, but that's not the case. Maybe in our lifetime. But the potential is great."
3D printing in manufacturing: Lessons for leaders
- While 3D manufacturing is still new and relatively expensive, its potential for consolidating many parts into one could make it a practical and even revolutionary alternative.
- More and more major manufacturers are turning to 3D printing, and suppliers need to pay attention to these changes.
- Small companies may find it cost effective to use 3D printing to create a small number of specialized products for their buyers or even to try out a new product before committing to it.
This article/content was written by the individual writer identified and does not necessarily reflect the view of Hewlett Packard Enterprise Company.