This month showcased many breakthroughs and announcements in the world of 3D printing. Let’s get started in Michigan.
Futurity reports on a stunning new 3D printing process developed by researchers at the University of Michigan. Apparently, it is 100 times faster than conventional 3D printing processes.
The limitation of 3D printing techniques utilizing layer-by-layer technology is that it “hasn’t been able to fill the gap on typical production timescales of a week or two.” As University of Michigan Associate Professor of Chemical Engineering Timothy Scott, who co-led the team of researchers explains: “using conventional approaches, that’s not really attainable unless you have hundreds of machines.”
Until now, that is…
The team’s new 3D printing method involves solidifying “liquid resin using two lights to control where the resin hardens – and where it stays fluid. This enables the team to solidify the resin in more sophisticated patterns. They can make a 3D bas-relief in a single shot rather than in a series of 1D lines or 2D cross-sections. Their printing demonstrations include a lattice, a toy boat, and a block M.”
By avoiding further solidification, “thicker resins – potentially with strengthening powder additives – can produce more durable objects. The method also bests the structural integrity of filament 3D printing, as those objects have weak points at the interfaces between layers.”
“The key to success is the chemistry of the resin. In conventional systems, there is only one reaction. A photoactivator hardens the resin wherever light shines. In the new system, there is also a photoinhibitor, which responds to a different wavelength of light. Rather than merely controlling solidification in a 2D plane, as current vat-printing techniques do, the team can pattern the two kinds of light to harden the resin at essentially any 3D place near the illumination window.”
The team has subsequently filed three patents for this innovative 3D printing process.
Elsewhere, Sky News reports on developments brought about by 3D printing in connection with spinal cord injuries. Researchers from the University of California, San Diego used 3D printing “to create the scaffolding around which stem cells can be implanted. [This] helped rats to regain significant motor control in their hind legs.”
These implants “contain dozens of tiny channels, just 200 micrometers wide.” This miniscule size helps “guide neural stem cells and axon growth along the spinal cord injuries.” These scaffolds have biocompatible designs, so “the body’s blood vessel system can naturally grow so the nerve fibers are kept alive and fed with nutrients as well as discharge waste.”
These implants can be 3D printed in less than two seconds for each device, according to the team. They published their results in the scientific journal Nature. During their research, they were able to “print a spinal cord loaded with neural stem cells. In the tests on rats, the scaffolds helped the animals regrow tissue and the stem cells nerve fibers inside the scaffolding expanded out into the host spinal cord.”
Trained Doctor and scientist, who directs the Translational Neuroscience Institute at UC San Diego School of Medicine, Professor Mark Tuszybski, who co-authored the paper, explains: “we’ve progressively moved closer to the goal of abundant, long-distance regeneration of injured axons in spinal cord injury, which is fundamental to any true restoration of physical function…the new work puts us even closer to the real thing…the 3D scaffolding recapitulates the slender, bundled arrays of axons in the spinal cord. It helps organize regenerating axons to replicate the anatomy of the pre-injured spinal cord.”
From spinal cords to space:
3D Printing Industry reports on a startling new announcement made by China’s National Space Administration back in mid-January. Apparently, CNSA has “announced plans to be the first country to establish a base on the moon” using 3D printing to create the housing.
This announcement was made by officials in Beijing at a press conference for the State Council Information Office (SCIO). This follows on the heels of the “Chinese lunar exploration mission, Chang’e 4, which achieved the first soft landing on the far side of the Moon at the beginning of” 2019.
Deputy Head of CNSA Wu Yanhua, along with announcing “the launch of another lunar exploration (Chang’e 5) at the end of the year,” also added: “we hope to test some technologies, and do some exploring for the building of a joint lunar base shared by multiple countries. For example, can we build houses on the moon with lunar soil using 3D printing technology?” The agency also “has plants to send a probe to Mars in 2020.”
This international moon colonization plan utilizing the wonders of additive manufacturing’s many positive qualities is actually quite fascinating. Already, the United States and the International Space Station have been utilizing many of 3D printing’s facets – and it would appear China is now enthusiastically jumping on board as well.
Time will tell if a lunar colony will one day be fully 3D printed and functional.
Back here on Earth, Popular Mechanics reports on the extended role 3D printing is taking when it comes to the maintenance of F-22 Stealth Fighter jets. This work is being done at the Ogden Air Logistics Complex at Hill Air Force Base in Utah.
“The U.S. Air Force has printed and installed a new titanium replacement piece for the F-22 Raptor stealth fighter…the piece in question is a fairly minor part – a bracket installed in a kick panel in the aircraft’s cockpit. Originally made from aluminum, the parts are replaced 80 percent of the time during Raptor maintenance. This new part is made from titanium powder and uses a laser-based powder bed fusion process.”
The benefits of a titanium piece is it won’t erode as aluminum pieces would. Aircraft maintenance can be slow and almost impossible to find spare parts for planes no longer in production, like the F-22. “But 3D printing allows the Air Force to quickly manufacture whatever parts it needs. The Air Force says if this bracket works out, future orders for the part could be filled in just three days…in addition to the bracket, there are five other parts waiting to go into 3D printing production for the F-22.”
The approval process is rigorous. As a Lockheed Martin Manager involved in the project describes: “we had to go to engineering, get the prints modified, we had to go through stress testing to make sure the part could withstand the loads it would be experiencing – which isn’t that much, which is why we chose a secondary part.”
Hopefully, this process is worth the extra usability 3D printing evidently provides to aircraft like the F-22.
Tune in next month for another round up of 3D printing news!
Quotes Courtesy of Futurity, Sky News, 3D Printing Industry, and Popular Mechanics
Image Courtesy of Futurity