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A Fatigue Life Approach for Additively Manufactured Structures

  • Rainer WagenerEmail author
  • Benjamin Möller
  • Matilde Scurria
  • Thilo Bein
Conference paper
  • 482 Downloads
Part of the The Minerals, Metals & Materials Series book series (MMMS)

Abstract

The relevance of the additive manufacturing technology is steadily growing, especially for metallic structures. In order to exploit the lightweight design potential for cyclically loaded safety parts in industrial applications, tools and methods are required to describe the fatigue behavior and the impact of the different exposure strategies on the cyclic properties as well as on the endurance. Furthermore, a fatigue approach has to secure the transfer of the cyclic behavior derived by the use of specimens to arbitrary structures and loading conditions. Therefore, the nominal stress concept and the local strain-based notch concept will be reviewed in order to check their applicability for additively manufactured structures. At the end, a modified fatigue approach, which takes into account the main influences on the fatigue and fulfills the industrial requirements with respect to an optimized computation time and validity of the fatigue approach, will be derived. The use of the Incremental Step Test to derive the cyclic stress-strain behavior and the Fatigue Life Curve enables to consider the influence of the load time histories at different maximum stress amplitudes, as well as a continuous fatigue approach from the Low Cycle Fatigue up to the Very High Cycle Fatigue regime.

Keywords

Representative structure elements Structure stress Structure strain Fatigue life curve Size effects Transfer functions 

Notes

Acknowledgements

The research and development project ‘BadgeB’ that form the basis for this publication is funded within the scope of the “Additive Fertigung—Individualisierte Produkte, komplexe Massenprodukte, innovative Materialien” by the Federal Ministry of Education and Research and managed by the KIT project management agency “Projekträger Karlsruhe—Produktion und Fertigungstechnologien”. The authors are responsible for the content of this publication.

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Copyright information

© The Minerals, Metals & Materials Society 2020

Authors and Affiliations

  • Rainer Wagener
    • 1
    Email author
  • Benjamin Möller
    • 1
  • Matilde Scurria
    • 1
  • Thilo Bein
    • 1
  1. 1.Fraunhofer Institute for Structural Durability and System Reliability LBFDarmstadtGermany

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