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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 | O C T O B E R 2 0 1 7 9 stall a self-contained continuous-ion- exchange/continuous-ion-chroma- tography pilot plant in Pennsylvania, and to determine the economic vi- ability of producing scandium and other REEs associated with coal waste. www.ems.psu.edu. SHAPE MEMORY METALS RESIST EARTHQUAKES Researchers at Tohoku University, Japan, discovered an economical way to improve theproperties of some shape memory metals. The newmethod could enablemass production of thesemetals for a variety of applications, including earthquake-resistant construction ma- terials. Most metals are made of a large number of crystals but, in some cases, their properties improve when they are formed of a single crystal. Typically, single-crystal metals are expensive to produce. The Tohoku team developed a cheaper production method that takes advantage of abnormal grain growth. By using this method, crystals grow ir- regularly, some at the expense of oth- ers, when exposed to heat. Heat treatment causing a grain to rapidly grow into a large single crystal. The technique involves several heating and cooling cycles that result in a sin- gle-crystal metal bar 70 cm in length and 15mm indiameter—very large com- pared to current shape memory alloy bars. To produce the large single-crys- tal metal bar, an alloy made of Cu, Al, and Mn is heated to 900°C then cooled to 500°C, five times, followed by four cy- cles of heating to 740°C then cooling to 500°C. Finally, the metal is heated one last time to 900°C. Increasing the size of the material’s crystals drastically en- hances its elasticity, while altering the shape greatly strengthens it—making it attractive for building structures that can withstand earthquakes. www.tohoku.ac.jp .