12 Watching High-Cycle Fatigue with Automated Scanning Electron Microscope Experiments 75 Fig. 12.1 Example of in situ SEM fatigue test performed on nanocrystalline Ni-Fe. The tests were performed inside of a JEOL IT300HR SEM (a) which housed a custom piezoelectric fatigue stage (b). Images were acquitted automatically in the SEM utilizing a custom Basic Image Recording Device (c). Fatigue loads were applied according to the schematic in (d) where 1000 fatigue cycles were applied at fixed loads, and then the loading was paused at the mean load to acquire an image. The progression of crack propagation in nanocrystalline Ni-Fe can be observed at different total fatigue cycles, N(e) Acknowledgments This work was funded by the United States Department of Energy (DOE), Office of Basic Energy Sciences (BES) (Grant No. 15013170), Division of Materials Science and Engineering. The authors acknowledge use of microscopy facilities at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the US DOE Office of Science by Sandia National Laboratories. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the US Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525. Any subjective views or opinions that might have been expressed in the chapter do not necessarily represent the views of the US Department of Energy or the United States Government. References 1. Campbell, F.C.: Elements of Metallurgy and Engineering Alloys. ASM International, Materials Park (2008) 2. Gurney, T.R.: Fatigue of Welded Structures. CUP Archive, Cambridge (1979) 3. Hosford, W.F.: Mechanical Behavior of Materials. Cambridge University Press, Cambridge (2010) 4. Stephens, R.I., Fatemi, A., Stephens, R.R., Fuchs, H.O.: Metal Fatigue in Engineering. Wiley, New York (2000) 5. Hertzberg, R.W., Hauser, F.E.: Deformation and fracture mechanics of engineering materials. J. Eng. Mater. Technol. 99(1), 96 (1977)
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