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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 | A P R I L 2 0 2 0 1 3 The NIST mechanophore research also found that existing testing was unintentionally damaging the mate- rial’s strength. This led designers and engineers to overdesign FRPs. Using the mechanophore could bring down energy and manufacturing costs and increase the ways these materials are used in industry. nist.gov. TESTING GRAPHENE’S FATIGUE RESISTANCE New research from the University of Toronto has revealed that graphene is highly resistant to fatigue—able to withstand more than a billion cycles of high stress before it breaks. The intrin- sic strength of graphene has been mea- sured at more than 100 gigapascals, among the highest values recorded for any material. To find out how graphene would stand up to repeated stressed, the research team used an approach that included both physical experiments and computer simulations. The team also tested a related ma- terial, graphene oxide, which has small groups of atoms such as oxygen and hydrogen bonded to both the top and bottom of the sheet. Its fatigue behav- ior was more like traditional materials, in that the failure was more progressive and localized. This suggests that the simple, regular structure of graphene is a major contributor to its unique properties. In terms of commercial applica- tions, the researchers say that graphene- containing composites—mixtures of conventional plastic and graphene— are already being produced and used in sports equipment such as tennis rack- ets and skis. In the future, such materials may begin to be used in cars or in aircraft, By stretching graphene across the million tiny holes embedded in a silicon chip, scientists can measure its resistance to mechanical fatigue. Courtesy of Daria Perevezentsev/University of Toronto Engineering. where the emphasis on light and strong materials is driven by the need to re- duce weight, improve fuel efficiency, and enhance environmental perfor- mance. utoronto.ca .