Dokument-ID Dokumenttyp Autoren/innen Persönliche Herausgeber/innen Haupttitel Abstract Auflage Verlagsort Verlag Herausgeber (Institution) Erscheinungsjahr Titel des übergeordneten Werkes Jahrgang/Band ISBN Veranstaltung Veranstaltungsort Beginndatum der Veranstaltung Enddatum der Veranstaltung Ausgabe/Heft Erste Seite Letzte Seite URN DOI Lizenz Datum der Freischaltung OPUS4-50470 Zeitschriftenartikel Laquai, René; Müller, Bernd R.; Kasperovich, G.; Requena, G.; Haubrich, J.; Bruno, Giovanni Classification of defect types in SLM Ti-6Al-V4 by X-ray refraction topography Porosity in additively manufactured materials, such as laser powder bed fusion Ti-Al6-V4, can play an important role in their mechanical performance. Not only the total porosity but also the shape/morphology of the individual pores need to be considered. Therefore, it is necessary to determine the distributions of different defect types (especially fusing defects and keyhole pores) and their dependence on process parameters. We show that synchrotron X-ray refraction radiography allows analysis of large samples (up to several millimeters) without compromising the detectability of submicrometer defects. Correspondingly, a classification tool is introduced that is able to quantitatively distinguish defects such as keyhole pores and binding defects with a confidence level of 94 %, even when the shape cannot be discerned because of limited spatial resolution. West Conshohocken, PA ASTM International 2020 Materials Performance and Characterization 9 1 82 93 10.1520/MPC20190080 2020-03-02 OPUS4-43404 Zeitschriftenartikel Laquai, René; Müller, Bernd R.; Kasperovich, G.; Haubrich, J.; Requena, G.; Bruno, Giovanni X-ray refraction distinguishes unprocessed powder from empty pores in selective laser melting Ti-6Al-4V For the first time, X-ray refraction techniques are proven for the identification of void formation in Ti-6Al-4V parts produced by selective laser melting. The topology and volume fraction of pores are measured in samples produced with different laser energy density. Unique X-ray refraction methods identify different kinds of defects, characteristic to the regions below and above the Optimum laser energy density, namely unprocessed powder (unmolten powder particles, balling effect, and Fusion defects) from empty keyhole pores. Furthermore, it is possible to detect small inhomogeneities (voids or cracks) with sizes below the spatial resolution of optical microscopy and X-ray computed tomography. London, UK Taylor & Francis Group 2018 Materials Research Letters 6 2 130 135 urn:nbn:de:kobv:b43-434041 10.1080/21663831.2017.1409288 http://creativecommons.org/licenses/by/3.0/de/deed.de 2017-12-12