Connecting Diffraction-Based Strain with Macroscopic Stresses in Laser Powder Bed Fused Ti-6Al-4V

Metallurgical and Materials Transactions A, vol. 51, pp. 3194–3204

Abstract

Abstract The laser powder bed fusion (LPBF) production process often results in large residual stress (RS) in the parts. Nondestructive techniques to determine RS are badly needed. However, a reliable quantification of macro-RS (i.e., stress at the component level) by means of diffraction-based techniques is still a great challenge, because the link between diffraction-based strain and macro-RS is not trivial. In this study, we experimentally determine (by means ofin-situsynchrotron radiation diffraction) this link for LPBF Ti-6Al-4V. We compare our results with commonly used models to determine the so-called diffraction elastic constants (DECs). We show that LPBF materials possess different DECs than wrought alloys, simply because their microstructural and mechanical properties are different. We also show that the existing models can be used to calculate DECs only if high accuracy of the RS values is not required. If the peculiarities of the microstructure have to be taken into account (as is the case of additively manufactured materials), a radically new approach is desirable.

Authors 10

1. Tatiana Mishurova corresponding

   Federal Institute For Materials Research and Testing

   Affiliation as printed

   Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany

2. Katia Artzt

   Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)

   Affiliation as printed

   Institute of Materials Research, German Aerospace Center (DLR, Deutsches Zentrum für Luft -und Raumfahrt), Cologne, Germany

3. Jan Haubrich

   Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)

   Affiliation as printed

   Institute of Materials Research, German Aerospace Center (DLR, Deutsches Zentrum für Luft -und Raumfahrt), Cologne, Germany

4. Sergei Evsevleev

   Federal Institute For Materials Research and Testing

   Affiliation as printed

   Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany

5. Alexander Dominic Evans

   Federal Institute For Materials Research and Testing

   Affiliation as printed

   Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany

6. Matthias Meixner

   Helmholtz-Zentrum Berlin für Materialien und Energie

   Affiliation as printed

   Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Berlin, Germany

7. Itziar Serrano‐Munoz

   Federal Institute For Materials Research and Testing

   Affiliation as printed

   Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany

8. Igor Sevostianov

   New Mexico State University

   Affiliation as printed

   Department of Mechanical and Aerospace Engineering, New Mexico State University, Las Cruces, USA

9. Guillermo Carlos Requena Aachen

   Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR) · RWTH Aachen University

   Affiliation as printed

   Institute of Materials Research, German Aerospace Center (DLR, Deutsches Zentrum für Luft -und Raumfahrt), Cologne, Germany

   Metallic Structures and Materials Systems for Aerospace Engineering, RWTH Aachen University, Aachen, Germany

10. Giovanni Bruno

    Federal Institute For Materials Research and Testing · University of Potsdam

    Affiliation as printed

    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany

    Institute of Physics and Astronomy, University of Potsdam, Potsdam, Germany