July/August_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 | J U L Y / A U G U S T 2 0 1 8 1 2 PROCESS TECHNOLOGY Army researchers imagine a rotorcraft concept with reactive reinforcements that increase their mechanical behavior upon exposure to UV light. Courtesy of U.S. Army. SIMPLER RECYCLING FOR RARE EARTH MAGNETS A new recycling process developed at the DOE’s Critical Materials Institute, Ames, Iowa, turns discarded hard disk drive (HDD) magnets into new magnet material and addresses both the eco- nomic and environmental issues typ- ically associated with mining e-waste for valuable materials. HDDs are the most common source of valuable rare earth magnets in the global electronics waste stream and have a relatively cen- tralized scrap source. “There are a lot of ways to go about getting the rare earth elements out of e-waste, and some of them are very ef- fective, but some create unwanted by- products and the recovered elements still need to be incorporated into a new application,” says scientist Ryan Ott. “Here we have eliminated as many pro- cessing steps as we can, and go straight These reactive reinforcing agents are then embedded in a polymer. Finally, UV light exposure causes a chemical reaction, resulting in increased inter- action between the reinforcing agents and the polymer. After a five-minute ex- posure to UV light, research shows that these composite materials could be- come 93 percent stiffer and 35 percent stronger. Researchers say the chemistry used here is generally applicable to a variety of reinforcement and polymer combinations, thereby expanding the utility of this control method to a wide range of material systems. Some par- ticularly attractive rotorcraft design op- tions associated with lower mechan- ical loads and vibration are not cur- rently achievable due to limitations in structural damping in hingeless blade or wing structures. Future structures based on this work may help lead to new composites with controlled struc- tural damping and lowweight, enabling designs such as soft in-plane tiltrotors. arl.army.mil , umd.edu . from the discarded magnet to an end product, which is a new magnet.” Scrapped HDD magnets are col- lected and protective coatings are re- moved. Magnets are crushed into pow- der, which is then deposited on a sub- strate using plasma spray to synthe- size coatings that are 0.5 to 1 mm thick. Properties of the end product are cus- tomizable depending on processing controls. The new magnetic material can- not retain the exceptional magnet- ic properties of the original material. However, it potentially offers an eco- nomical choice where the performance of a high-strength rare earth magnet is not required, but lower performance magnets like ferrites are insufficient. The method is also an efficient way to produce strong magnets for small devices like handheld electronics. cmi.ameslab.gov. NEW TECHNIQUE ENABLES ADAPTIVE MATERIALS Engineers at the U.S. Army Re- search Laboratory, Adelphi, Md., and the University of Maryland, College Park, have developed a technique that causes composite materials to quick- ly become stiffer and stronger when exposed to ultraviolet (UV) light. This on-demand control of composite be- havior could enable a variety of new ca- pabilities for future Army rotorcraft de- sign, performance, and maintenance. The technique consists of attach- ing UV light-reactive molecules to rein- forcing agents like carbon nanotubes. Plasma torch depositing recycledmagnet material. Courtesy of Ames Lab. BRIEF Bodycote, U.K., signed a 15-year contract with Rolls-Royce’s civil aerospace business. The contract is expected to be worth over $215 million in incremental revenues over the entire period. Bodycote will provide thermal processing ser- vices, which include specialized vacuum heat treatment and hot isostatic pressing, supporting Rolls-Royce’s turbine blade casting facilities in Derby and Rotherham, U.K. bodycote.com , rolls-royce.com .