Preprint / Version 1

Impact of Process Variables and Loading Conditions on the Fatigue Life of EB-PBF-Manufactured Ti6Al4V Alloys

Authors

  • Costanzo Bellini University of Cassino and Southern Lazio
  • Filippo Berto Sapienza University of Rome
  • Rosario Borrelli Italian Aerospace Research Centre
  • Vittorio Di Cocco University of Cassino and Southern Lazio
  • Paolo Di Giamberardino Sapienza University of Rome
  • Stefania Franchitti Italian Aerospace Research Centre
  • Daniela Iacoviello Sapienza University of Rome
  • Stefano Natali Sapienza University of Rome
  • Daniela Pilone Sapienza University of Rome
  • Carolina Schillaci Sapienza University of Rome

DOI:

https://doi.org/10.62679/ESIAM26_1

Keywords:

Ti6Al4V, Fatigue Behaviour, Load Ratio, Energy Density

Abstract

Additive Manufacturing allows the fabrication of complex shape parts, but the manufacturing processes may introduce defects that undermine the mechanical performance. In the presented study, the influence of selected process parameters and testing conditions on the fatigue life of Ti6Al4V alloys produced by Electron Beam-Powder Bed Fusion (EB-PBF) has been studied.

To study the effects of process parameters, the EB-PBF machine was operated in manual mode, bypassing proprietary manufacturing algorithms. Moreover, various load ratios were considered for fatigue tests conducted under constant-amplitude loads.

The results established a direct relationship between energy density, microstructure, and fatigue resistance. It was found that the beam current and the scan speed significantly determined the energy density of the process and, consequently, the material porosity and density, so affecting the mechanical performance. These findings indicate that careful selection and control of manufacturing parameters can enhance fatigue properties in EB-PBF components. This information can be used to support the development of AI-based optimisation strategies to predict stress-related behaviour and minimise defects, such as cracking and residual stress.

References

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Posted

30-04-2026

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Data Availability Statement

Research data available upon request 

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Copyright (c) 2026 Costanzo Bellini, Filippo Berto, Rosario Borrelli, Vittorio Di Cocco, Paolo Di Giamberardino, Stefania Franchitti, Daniela Iacoviello, Stefano Natali, Daniela Pilone, Carolina Schillaci (Author)

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