Among them: a kidney printed from a sample of the patient’s cells, low-volume parts with built-in pedigrees
As additive manufacturing (AM) moves from prototypes to mass production, manufacturers are setting their sights on the holy grails—the products and processes that will be game-changers. Many game-changers are already in play.
“There is a fork in the road,” Met-L-Flo President Carl Dekker said. “Some people have started trailblazing. Most people are tiptoeing ahead quietly because they know how competitive it is. We have amazing things printed now in the public sector that you can see. One can only guess how many pieces are in development.”
“One of the things we saw early on in the AM area that was obvious to us was there were a lot of companies really good at making one-off products,” Ashley Eckhoff of Siemens, said. “You can make prototypes all day long because they have less stringent requirements than end products. We saw there was a real need in the industry to move toward actual production of parts. We started a multi-year learning process, a journey from prototypes to actual production of parts. We are getting to a quality, repeatable process that truly allows people to do industrial production with AM rather than these one-off products.”
For products, consider additively manufactured organs widely available for transplant. This particular holy grail is closer than many envision.
“Kidneys are our ultimate goal,” Prellis Biologics CEO Melanie Matheu said. “This is our vision—to have there no longer be a waiting list for organ donations.”
As for processes, the rapidly maturing additive manufacturing process already consolidates components,reduces weight, cuts costs, increases throughput, reduces maintenance and makes inspections easier.
In aerospace and defense, each component subtracted lowers the buy-to-fly ratio—the amount of raw material needed to produce the end part.
“Ultimately, the amazing opportunities are out there,” Dekker said. “Think about part consolidation and weight reduction. If you can remove 50 percent of the parts on an aircraft, you can do an amazing cost reduction just because of the amount of inspection, re-inspection, management, maintenance of materials, requirements, documentation and recertifications that go through the entire supply chain.”
Welcome to 3D ‘painting’
Within AM, a new type of material, 3D “paint,” combined with a new 3D-painting process now make it possible for any extrusion-based AM printer to print any material at room temperature, Dimension Inx CTO Adam Jakus said.
“People talk about 3D printers for metals, polymer 3D printers, etc.,” he said. “The hardware is defined by the material used. This is no longer the case with 3D-painting. There is nothing special about the printers. This is all about the 3D-Paint, its composition and properties that make this possible.”
Kidneys would be inside jobs
In the medical sector, researchers at Prellis Biologics are working on creating kidneys printed from a biopsy-sized sample of the patient’s own cells, Matheu said.
The National Kidney Foundation says more than 100,000 people are waiting an average of 3.6 years for a kidney transplant. For them, such a kidney will be a life-changer.
Since the printed kidney will be native to the patient’s body, these patients will not need to take immuno-suppressant drugs or face a higher risk of dying from cancer, according to several studies published by the Journal of the American Medical Association.
Prellis is targeting kidneys first. “We’re very close—three to five years,” from testing solid human organ transplants in large animals as a precursor to FDA trials, Matheu said. “This is a tremendous advancement in a field that routinely cites organ replacements as decades away.”
Until now, one challenge has been additively manufacturing capillaries, the tiny—10 micrometers in diameter, one-tenth the size of a human hair—blood vessels that carry oxygen and other nutrients to tissues and remove waste, she said.
“Building capillaries with typical 3D printing methods is not possible,” Matheu said. “To get real human tissue, we need to print on the micron level. That’s why I founded this company. We found a way to do that.”
Prellis uses laser light to create super-high resolution for 3D printing at the micrometer level, she said.
Another challenge was time. “There’s a tradeoff between speed and resolution,” Matheu said. “Using a single point of laser light to build something like an organ takes months. It’s like building a house with grains of sand.”
Thousands of points of light
To partially decouple speed and resolution, Prellis added more laser lights.
“Instead of using one point of laser light per second, we use 150,000 points of laser light per second,” she said. “New optics will project a million points of light per second. We are working on designs to print 12 million points of light per second.”
When the 12 million points of light milestone is achieved, Prellis should be able to print a human sized organ with all the necessary vasculature in about 24 hours, she added. “That’s our ultimate goal.”
Another challenge is cost. “We’re very conscious of cost,” Matheu said. “The most expensive part of our manufacturing process is generating and seeding the human cells.
“Just matching and getting a kidney from a donor costs about $150,000. Transplants for our first few patients probably will cost twice that. Our ultimate goal is to match the cost of procuring a kidney or liver for a transplant. Our vision is to give people their lives back—not make them beholden financially.”
With transplants created from their own cells, patients will not need to take expensive ($20,000/year) immune-suppressant drugs that lead to a higher risk of dying from cancer, she said.
If for some reason the organ recipient’s own cells are not suitable, perhaps because of illness, the barriers to organ donation will be low compared with now, she said. “Donors don’t have to give up their own kidneys, just a few cells. Pretty much everyone becomes an organ donor. The registry for organ donors has the capacity to go through the roof.”
Beyond kidneys, Prellis is working on printing small livers (a liver doesn’t need to be full-size to do its job) and pancreatic islets, also called Langerhans, the specialized cells in the pancreas that produce insulin. “The patient could be their own donor for cells that could begin to produce insulin,” Matheu said.
Prellis also is leveraging its speed, resolution and ability to create true 3D tissue to help researchers who test drugs and other products, she said.
“The standard research lab or pharmaceutical lab doesn’t have access to high-end 3D printing techniques,” she added. “Other labs also are very slow and may take four days to get it right. We can print in 30 minutes.”
With other techniques, the size limit for such tissue scaffolding is 200 microns, Matheu said. Larger than that and oxygen won’t diffuse.
By using a vascular scaffold that allows oxygen to diffuse, Prellis can build tissue scaffolding up to 2 millimeters—300 times the size, she said. Instead of studying 300 or 400 cells, researchers can test millions of cells. Prellis is also able to create these tissue scaffolds in true 3D.
These advances mean that drug trials will yield more accurate, trustworthy results, Matheu added.
Muscle-. bone-type tissue from one printer
Dimension Inx’s 3D-Paint is engineered so as materials can easily be combined and printed on any extrusion-based AM printer, Jakus said.
“From a technical standpoint, these materials are paint—particles suspended in solvents with a binder,” he said. “It’s all about the paint, its composition and properties that make this possible.”
Dimension Inx is working in the biomedical sector with complex tissue and organ engineering, as well as in energy and advanced structures, creating hundreds of 3D-Paint materials compatible with using AM extrusion processes at room temperature—without the need for powder-beds, resin-baths, cross-linking, curing, heating, cooling or drying.
Many existing AM printers are compatible with Dimension Inx’s 3D-Paint.
“We can print muscle-type tissue, bone-type tissue on the same machine,” Jakus said. “Our technique lets us take what people use for bioprinting and be able to print metals, ceramics, anything else. It’s as simple as loading a color printer cartridge on a 2-D printer. If you want to print red, make sure red is loaded. If you want to print bone, you load bone.”
One of Dimension Inx’s materials is “tissue papers,” comprised primarily of decellularized tissue and organ that contain both chemical and structural biological cues inherent to the biological tissue from which they are derived, such as kidney, liver, heart and uterus.
Dimension Inx can combine several types of tissue—for example bone, muscle and tendon—into one material more similar to what naturally occurs within the human body, Ramille N. Shah, chief scientific officer, said. She and Jakus cofounded the firm.
Dimension Inx focused early on what it calls hyperelastic bone because bone is a tissue worked on for the longest time in tissue engineering, Shah said. Dimension hopes to have FDA approval by the end of this year.
“We’re beyond prototypes and now in a process of scaling and reducing costs,” she said. “A lot of it is dictated by the market—there’s a clear market for bone implants and bone grafts.”
The biggest market demand within the medical sector. and the easiest pathway to FDA approval. is for off-the-shelf products, Shah said.
For example, surgeons could get an off-the-shelf, hyperelastic bone in a standard shape and then easily trim and customize that bone to meet an individual patient’s bone defect or void, she said. “That is what surgeons like the most—to be able to shape the hyperelastic bone in the OR.”
Cleft palates addressed
Another need for AM bone is for children with cleft palates.
Although cadaver bone is used for this and similar surgeries for adults, children have not developed a strong immune system to handle the side effects from putting someone else’s bone in their bodies, Jakus said. Although in some cases, surgeons can use the patient’s own bone to fill a bone void, that surgery leads to more pain and a longer recovery time.
But standard synthetic materials, such as ceramic granules and putties commonly used, do not always and reliably remain in place, he said.
Dimension Inx can use 3D-painting to create a slightly larger palate implant to allow surgeons to better fit the implant in place.
The company also has many more sophisticated materials for orthopedic, liver, kidney and even “3D-graphene” for cardiac applications, Jakus said.
What was 20 components can now be 1
To see clearly what is coming, of course it is often necessary to examine successes in the recent past.
In January, GE Aviation’s facility in Auburn, Ala., which now has 40 3D printers, used additive manufacturing to make its 30,000th fuel nozzle tip for the LEAP jet engine, Chris Schuppe, general manager of GE Additive AddWorks, said.
Getting there was not a quick trip: GE started prototyping fuel nozzles in the late 2000s. It produced the first nozzle tip in 2015 and began mass production in 2016.
Using AM reduces waste, reduces weight and enables the fuel nozzle tip to be made in a fraction of the time, he said, declining to be more specific.
A traditionally manufactured fuel nozzle consists of 20 different parts, all of which must withstand very cold fuel being injected into an environment as hot as 1,400 degrees F, which then heats up to well over 3,000 degrees, Schuppe said.
Reducing the number of nozzle components from 20 discrete parts to one is huge because every component and every place where pieces come together is an opportunity for problems or failure, he said. If any one part fails, the entire nozzle fails.
“It’s a very challenging environment in terms of tolerance and stress on parts,” Schuppe said. “Typically, all 20 pieces are welded and braced to fit together. All of those welds create opportunities for defects, stress and other problems. Now we’ve changed from a 20-piece assembly down to a single piece assembly with much finer control on tolerances and consistencies.”
Using additive to create the nozzle enabled GE to reduce the weight by 25 percent.
Such weight savings create multiplier effects.
“If you have a buy-to-fly ratio of 12 pounds of material to make a 1-pound part and you get to a ¾-pound part, you just decreased the amount of raw materials and the weight of that part on other systems,” Dekker said.
As for monetary savings, often the expenses to build a part add up much higher than the actual part, he said.
“You hear about the $400 hammer—and you’re right [that] no hammer should be that expensive—but the requirements imposed to ensure, for example, that hammer is manufactured from the right natural minerals, from the right mining locations can add an immense amount of paperwork and hurdles, which justifies the cost,” Dekker said. “You have to know all the materials and components are correctly certified.”
Additional savings and increased efficiencies come from reducing the tooling required to manufacture a complex part, he said.
“Before embracing additive manufacturing, you may have had to make extensive tooling to produce the geometrics of a part. It may have been to the point where somebody looked at a product and said, ‘There’s no way we’re going to quote that because the amount of tooling required would be too extensive.’ The buyer will have to go to whoever made the original part. Now you have the opportunity to make replacement parts that weren’t feasible before.”
Low-volume parts with built-in pedigrees
The military has a growing need to produce low-volume parts in ways that the ability to verify that the parts meet specifications can be embedded within the part itself.
Additive manufacturing makes that possible, Dekker said.
“We don’t want our warfighters out there with unapproved products that could be causing them to risk their lives,” he added.
Lessons learned from the fuel nozzles can be applied to larger structures, Schuppe said.
“The same things we did on something as small as a fuel nozzle, regarding fluid mixing and control, also apply to larger structures like rocket engines,” he said. “We see a path toward larger machines, larger applications. Ultimately, you could print the entire engine or other major systems.”
In energy, smaller can definitely be better
In the energy sector, one pain point has been the high expense of servicing a wind turbine, Schuppe said.
“The blades are over 100 meters long,” he said. “Because they’re so big, you have to hire a crane or a boat with a crane to replace a part. Cranes cost $250,000 a day to rent. If they can make the heat exchanger 20 percent smaller by using additive manufacturing, that takes it from crane maintenance to tower maintenance.”
Siemens is using AM and generative design—using computer simulations, IoT and product life cycle monitoring to create hundreds of potential designs—within the energy sector to create innovative products, John Nixon, director of Siemens PLM Software, said.
In addition to being unique and innovative, the resulting generative designs often are complex and difficult to produce using standard manufacturing processes, he said.
“AM allows you to manufacture really complex parts and systems that could not be manufactured using the old manufacturing methods,” he added.
One example is burners used in energy generation.
Siemens’ intelligent burner manufacturing (what it calls i-BuMa) reduced and simplified a 13-part system to one printed part, Eckhoff said.
Importantly, the process also reduced weight by 22 percent and cutting lead time from 26 weeks to three weeks, he added.
“Instead of being machined and welded, now it’s a single piece, printed and we’re able to get it into field much faster than the older ones,” he said.
Distributed micro AM factories favored
One holy grail for the energy sector that also could apply in other sectors is micro AM factories scattered around the world for distributed manufacturing, Nixon said.
“Think about all the distributed assets over large geographical areas—that’s a huge problem for downstream oil and gas,” he said.
“Instead of one big factory with every piece of equipment to ship inventory across the globe, you could have two printers and the associated equipment that goes with them closer to the point of delivery of the parts.”