3D printing or additive manufacturing is ongoing revolution in manufacturing with its potential to fabricate any complex object and is being utilized from aerospace components to human organs, textiles, metals, buildings and even food. 3D printing is also revolutionizing defence by printing small components to full drones on naval vessels, replacement parts for fighter aircrafts to printing ammunition. Substantial improvements have been made in 3D printing with the fabrication of 3D objects from metals, ceramics, plastics, and even multi-material capabilities.
NASA and the US military used 3D printed components to successfully test advanced prototype airplanes, spacecraft and even ground vehicles. In March 2016, the Navy successfully test launched three Trident II D5 Fleet Ballistic Missiles made by Bethesda, Maryland-based Lockheed Martin. The one-inch wide aluminum alloy connector backshell component protects vital cable connectors in the missile. The backshell component was designed and fabricated entirely using 3D design and 3D printing, a process that allowed Lockheed Martin engineers to produce the part in half the time it would take traditional methods.
According to John Burrow, deputy assistant secretary of the Navy for Research, Development, Test and Evaluation, additive manufacturing is at the core of the Pentagon’s Third Offset Strategy. “I will tell you, frankly…AM is the foundation for the Third Offset,” Marotto said. “Levering the technology as agnostic as it is…is really the key if you’re going to operate as a Marine Corps in a distributed ops environment. Everything from being able to print your own parts in stream…to printing your own UAVs for ISR, for weaponization, on site, custom made, with sensors to do that exact mission that you need at that exact moment.”
New 3D printers are being developed for increased speed and printing new materials which have defence applications. Military requires new type of 3D printers with high speed so that they can rapidly adapt to new missions such as during conflicts or after natural disasters. 3D printers are also required to print strategic materials like synthetic diamonds and carbon fibers.
Synthetic diamond is emerging as most versatile super material for defence that shall have significant effect in a variety of applications as diverse as high power radars, communications and electronic warfare systems, Directed Energy Weapons, MEMS applications, Aerospace applications and Quantum science among many others.
Xjet introduces ceramic nanoparticle
XJet has been making quite a stir in the 3D printing world this year, since the introduction of their unprecedented NanoParticle Jetting Technology back in April. NanoParticle Jetting is dramatically different than other metal 3D printing technologies, using liquid instead of powder to build metal parts as easily as any inkjet printing system. The liquid, which contains metal nanoparticles or support nanoparticles, is loaded into the printer as a cartridge and jetted onto the build tray in extremely thin layers of droplets. High temperatures inside the build envelope cause the liquid to evaporate, leaving behind metal parts with almost identical properties to traditionally manufactured metal parts.
NanoParticle Jetting Technology prints ceramic materials in the same way as metals. A liquid dispersion containing ceramic nanoparticles, contained in sealed cartridges, is loaded into the printer, where it is then jetted onto the build platform, just like any inkjet printer. The high temperatures inside the build envelope cause the liquid to evaporate, leaving layers of ceramic behind to form parts with the same mechanical properties as traditionally manufactured ceramics.
The advantages of NanoParticle Jetting, according to XJet, can be summed up as three major points: Details, dispersion and design freedom. The small size of the metal particles and the thinness of the layers allow for smaller details and thinner walls than other metal additive manufacturing technologies, and the cartridge delivery system provides safe and simple handling. Meanwhile, the unique support materials require no pre-design and are easily removed afterwards, enabling parts of almost any geometry to be printed.
“The expansion of NanoParticle Jetting to include ceramics will allow XJet to address an even wider range of applications, such as dental, medical and specific industrial applications,” said Dror Danai, Chief Business Officer, XJet. “At formnext we will demonstrate how the usage of ink-jet technology, and it’s very large tray, will encourage more industries to look at Ceramic Additive Manufacturing as an option for both customized parts and relatively large scale manufacturing of small parts.”
Lockheed Martin files patent for a synthetic diamond 3D printer
Inventor David G. Findley of Lockheed Martin, the aerospace company, have filed a patent for a new kind of 3D printer. The patent, describes a new way of 3D printing which would heating pre-ceramic polymer and nanoparticle filler to create synthetic diamond objects of pretty much any shape you can dream up.
“[The] method includes depositing alternating layers of a ceramic powder and a pre-ceramic polymer dissolved in a solvent. Each layer of the pre-ceramic polymer is deposited in a shape corresponding to a cross section of an object. The alternating layers of the ceramic powder and the pre-ceramic polymer are deposited until the layers of the pre-ceramic polymer form the shape of the object. The method includes heating the deposited ceramic powder and pre-ceramic polymer to at least a decomposition temperature of the pre-ceramic polymer. The decomposition temperature of the pre-ceramic polymer is less than a sintering temperature of the ceramic powder. The method further includes removing excess ceramic powder that the pre-ceramic polymer was not deposited onto.”
Technology breakthrough can result in massive increase in 2D and 3D printing speeds
A major technological advance in the field of high-speed beam-scanning devices has increased the speed of 2D and 3D printing by up to 1000 times, according to researchers in Penn State’s College of Engineering.
Using a space-charge-controlled KTN beam deflector — a kind of crystal made of potassium tantalate and potassium niobate — with a large electro-optic effect, researchers have found that scanning at a much higher speed is possible.
“Basically, when the crystal materials are applied to an electric field, they generate uniform reflecting distributions, that can deflect an incoming light beam,” said Shizhuo Yin, professor of electrical engineering in the School of Electrical Engineering and Computer Science. “We conducted a systematic study on indications of speed and found out the phase transition of the electric field is one of the limiting factors.”
To overcome this issue, Yin and his team of researchers, Penn State graduate students Wenbin Zhu, Ju-Hung Chao, Chang-Jiang Chen and Robert Hoffman from the Army Research Laboratory in Maryland, eliminated the electric field-induced phase transition in a nanodisordered KTN crystal by making it work at a higher temperature. They not only went beyond the Curie temperature (the temperature in which certain materials lose their magnetic properties, replaced by induced magnetism), they went beyond the critical end point (in which a liquid and its vapor can coexist).
This increased the scanning speed from the microsecond range to the nanosecond regime and improved high-speed imaging, broadband optical communications, and ultrafast laser display and printing.
The group’s findings were published September in an issue of Nature Scientific Report, a British interdisciplinary journal.
Yin said technology like this would be especially meaningful in the medical industry — high-speed imaging would now be in real-time. For example, optometrists who use a non-invasive imaging test that uses light waves to take cross-section pictures of a person’s retina, would be able to have the 3D image of their patients’ retinas as they are performing the surgery, so they can see what needs to be corrected during the procedure.
Yin added that this research could benefit everyone, in that something being printed in 3D that once took an hour would now take seconds, and 20,000 pages printed in 2D would take one minute.
World’s First Carbon Fiber 3D Printer now ready to order
MarkForged founded by MIT aerospace engineer Greg Mark, has introduced revolutionary Mark One 3D printer, the world’s first 3D printer designed to print parts from continuous carbon fibers. Its patent pending Composite Filament Fabrication (CFF) process overcomes the strength limitations of traditional 3D printed materials, and enable 3D printing of continuous carbon fiber parts that are up to 20 times stiffer and five times stronger, than ABS plastic, the commonly 3D-printed material, and have a higher strength-to-weight ratio than CNC-machined 6061-T6 aluminum. Designers can choose between lightweight carbon fiber, low-cost fiberglass, abrasion resistant Kevlar or low cost and biodegradable PLA to print parts, tooling, and fixtures and can serve many applications from medical prosthetics to hobbyist drone manufacture.
DARPA plans OM program for high speed and high quality Manufacturing Processes
Uncertainties in materials and component manufacturing processes are a primary cause of cost escalation and delay during the development, testing and early production of defense systems. In addition, fielded military platforms may have unanticipated performance problems, despite large investment and extensive testing of their key components and subassemblies. These uncertainties and performance problems are often the result of the random variations and non-uniform scaling of manufacturing processes. These challenges, in turn, lead to counterproductive resistance to adoption of new, innovative manufacturing technologies that could offer better results.
Overcoming this shortcoming is necessary to enable reliable mass production of additively manufactured structures such as aircraft wings or other complex components of military systems, which must meet demanding specification requirements.
With its swift advance into the final phase of the DARPA OM program, Sigma Labs has announced that it has officially achieved the quality assurance that the Defense Department is looking for when using 3D printed metal. After completing Phase I and II in 2014 and earlier in 2016 respectively. Through this award, we’ll have the opportunity to demonstrate how our PrintRite3D software can be a key enabler for developing quality assurance standards for metal [3D printed] aerospace components.”
DARPA created the Open Manufacturing program to lower the cost and speed the delivery of high-quality manufactured goods with predictable performance. It aims to do so by creating a manufacturing framework that captures factory-floor and materials processing variability and integrates probabilistic computational tools, informatics systems and rapid qualification approaches. These newly developed concepts and approaches will be used to characterize and reduce the risk of new manufacturing technologies.
DARPA’s Open Manufacturing program seeks to solve this problem by building and demonstrating rapid qualification technologies that comprehensively capture, analyze and control variability in the manufacturing process to predict the properties of resulting products. Success could help unleash the potential time- and cost-saving benefits of advanced manufacturing methods for a broad range of defense and national security needs.
One of the four foundational areas in Open Manufacturing is Development of novel, rapid, robust manufacturing and fabrication processes that result in improved performance, reduced production times and more affordable manufacturing. Within this area, performers will attempt to demonstrate two specific technologies: metals additive manufacturing and the manufacturing of bonded composites structures.
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