September AMP_Digital

A D V A N C E D M A T E R I A L S & P R O C E S S E S | S E P T E M B E R 2 0 1 8 1 3 3D PRINTSHOP ROCKET SCIENCE CALLS FOR COOKIE DOUGH New research at Purdue Univer- sity is making it possible to 3D print extremely viscous materials with the consistency of clay or cookie dough. By applying high-amplitude ultrasonic vi- brations to the nozzle of the 3D printer, engineers were able to solve a problem that has plagued manufacturers for years. While other approaches involve changing the material composition, the Purdue team used a vastly differ- ent method. By vibrating the nozzle in a specific way, they reduced the friction on the nozzle walls, allowing the ma- terial to slide through. The team has printed items with 100-µm precision— better than most consumer-grade 3D printers—while maintaining high print rates. Solid rocket fuel is now being ex- plored as the first practical application. purdue.edu . MIT PRINTS MAGNETICALLY ACTIVATED STRUCTURES Engineers at the Massachusetts Institute of Technology (MIT) recent- ly designed and built soft, 3D-printed structures whose activities can be orchestrated with a magnet. The col- lection includes a smooth ring that wrinkles up, a long tube that squeez- es shut, a sheet that folds itself, and a spider-like grabber that can crawl, roll, jump, and snap together fast enough to catch a ball. researchers can make devices that quickly shift into intricate shapes and move around. Professor Xuanhe Zhao says the technique could be used to fabricate magnetically controlled bio- medical devices. “For example, we could put a structure around a blood vessel to control the pumping of blood, or use a magnet to guide a device through the GI tract to take images, extract tissue samples, clear a blockage, or deliver drugs to a specific location,” says Zhao. “You can design, simulate, and then just print to achieve various functions.” mit.edu . BACK TO SCHOOL WITH GE PRINTER PACKS The GE Additive Education Pro- gram (AEP) recently awarded polymer 3D printing packages focused on sci- ence, technology, engineering, art, and mathematics (STEAM) to more than 600 schools. Tailored to students in grades K-12, the goal is to build an understand- ing of 3D printing by networking stu- dents, machines, and content via an online platform called the Polar Cloud. The AEP has also donated more than 1000 polymer 3D printers to schools in 30 countries over the past two years, impacting more than 400,000 students. Packages include a Polar Cloud ac- count, Dremel Digilab 3D45 polymer printer, six rolls of replacement fila- ment, and lesson plans. ge.com . MIT researchers built structures from a new type of 3D-printable ink infused with tiny magnetic particles. Staff from XJet Ltd. of Israel were all smiles after showcasing their new AM system for metal and ceramic parts at the Youngstown Business Incubator in Ohio. Assistant professor Emre Gunduz uses ultrasonic vibrations to maintain a flow of material through the printer nozzle. Courtesy of Purdue University/Jared Pike. STEAM students benefit fromGE’s Additive Education Program. Courtesy of Syda Productions/Shutterstock.com. Researchers fabricated each de- sign from a new type of 3D-printable ink infused with tiny magnetic par- ticles. They fitted an electromagnet around the nozzle of a 3D printer, caus- ing magnetic particles to swing into a single orientation as ink is fed through. By controlling the magnetic orientation of individual sections in the structure,