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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 | F E B R U A R Y / M A R C H 2 0 1 9 9 intermetallic nanoparticles can greatly strengthen the alloy uniformly by im- proving deformation instability. And they say they have discovered the ideal formula for these complex nano- particles, which consists of nickel, co- balt, iron, titanium, and aluminum at- oms. The iron and cobalt atoms, which replace some of the nickel components, help to reduce the valence electron density and improve ductility. Further, the researchers found that replacing some of the aluminum with titanium largely reduces the impact of moisture in the air to avoid induced embrittle- ment in the new alloy. The team believes that the alloys developed with this strategy will per- form well in temperatures ranging from -200° to 1000°C. Thus, they can act as a solid developmental base for structural use in cryogenic devices, aerospace sys- tems, and beyond. www.cityu.edu.hk . structure where the atoms have a dis- ordered structure. In addition to the potential for transparent and far more bendable glass, some ZIFs contain large num- bers of functional pores that could be used for gas storage. Such metal- organic frameworks have been pro- posed as cages for hydrogen storage for fuel cell vehicles, catalysis, gas sep- aration, or even drug delivery. The re- searchers now plan to accelerate the design of these new glasses through modeling. psu.edu . NEW CLASS OF METAL- ORGANIC GLASSES Researchers from Penn State Uni- versity, State College, and Cambridge University, U.K., are exploring a new family of glasses that could combine the transparency of silicate glass with the nonbrittle quality of metallic glass. The newest class of glass-forming materials, zeolitic imidazolate frame- works (ZIF), has a structure in which metal ions are linked by organic li- gands. When heated within a limited range of high temperatures, some ZIF materials melt and reform into a glassy The new Al 7 Ti 7 alloy exhibits strength of 1.5 gigapascals and ductility as high as 50% in tension at ambient temperature. Courtesy of City University of Hong Kong. Computational model of porous ZIF glass. Courtesy of Yongjian Yang/Penn State.