Grain boundary characterization and energetics of superalloys

verfasst von: Michael D. Sangid, Huseyin Sehitoglu, Hans J. Maier, Thomas Niendorf
Abstract: In many engineering alloys, there exists a wide distribution of grain sizes; we investigate the role of grain boundaries as a strengthening mechanism in such a material. The coincidental site lattice (CSL) model is a powerful mathematical tool to characterize grain boundaries (GBs) and identify 'special' boundaries, which display beneficial mechanical behavior. We define the CSL and describe a detailed procedure to obtain this information from the grain orientation mapping via electron back scattering diffraction (EBSD). From this information, we show the evolution of the CSL for a nickel-based superalloy, Udimet 720 (U720), throughout various stages of processing (billet and forging) and experiments (tension, compression, and fatigue). A deeper level of understanding the GB's role in the mechanical behavior of the material is investigated through atomic simulations using molecular dynamics (MD) as the GB energy is determined for the most prevalent GBs within this material. The spatial map of the orientation and grain sizes measured from EBSD is linked to the GB energies calculated from MD. Based upon the large number of boundaries analyzed (29,035), there is a strong inverse correlation between GB energy and grain size for every specimen examined during the various processing and testing conditions.
Externe Organisation(en): University of Illinois Urbana-Champaign (UIUC)
Universität Paderborn
Typ: Artikel
Journal: Materials Science and Engineering A
Band: 527
Seiten: 7115-7125
Anzahl der Seiten: 11
ISSN: 0921-5093
Publikationsdatum: 27.07.2010
Publikationsstatus: Veröffentlicht
Peer-reviewed: Ja
ASJC Scopus Sachgebiete: Allgemeine Materialwissenschaften, Physik der kondensierten Materie, Werkstoffmechanik, Maschinenbau
Elektronische Version(en): https://doi.org/10.1016/j.msea.2010.07.062 (Zugang: Unbekannt)

BibTeX

@article{8487ccbf745a4efea6ac86aa0d8f15aa,
title = "Grain boundary characterization and energetics of superalloys",
abstract = "In many engineering alloys, there exists a wide distribution of grain sizes; we investigate the role of grain boundaries as a strengthening mechanism in such a material. The coincidental site lattice (CSL) model is a powerful mathematical tool to characterize grain boundaries (GBs) and identify 'special' boundaries, which display beneficial mechanical behavior. We define the CSL and describe a detailed procedure to obtain this information from the grain orientation mapping via electron back scattering diffraction (EBSD). From this information, we show the evolution of the CSL for a nickel-based superalloy, Udimet 720 (U720), throughout various stages of processing (billet and forging) and experiments (tension, compression, and fatigue). A deeper level of understanding the GB's role in the mechanical behavior of the material is investigated through atomic simulations using molecular dynamics (MD) as the GB energy is determined for the most prevalent GBs within this material. The spatial map of the orientation and grain sizes measured from EBSD is linked to the GB energies calculated from MD. Based upon the large number of boundaries analyzed (29,035), there is a strong inverse correlation between GB energy and grain size for every specimen examined during the various processing and testing conditions.",
keywords = "Coincidence site lattice (CSL), Electron back scattering diffraction (EBSD), Grain boundary energy, Molecular dynamics simulations, Nickel-based superalloys",
author = "Sangid, {Michael D.} and Huseyin Sehitoglu and Maier, {Hans J.} and Thomas Niendorf",
year = "2010",
month = jul,
day = "27",
doi = "10.1016/j.msea.2010.07.062",
language = "English",
volume = "527",
pages = "7115--7125",
journal = "Materials Science and Engineering A",
issn = "0921-5093",
publisher = "Elsevier BV",
number = "26",
}