Numerische und experimentelle Analyse eines drahtbasierten additiven Herstellprozesses

Translated title of the contribution: Numerical and Experimental Analysis of Wire Arc Additive Manufacturing

Raphael Berger

Research output: ThesisMaster's Thesis

Abstract

This master thesis deals with the numerical and experimental analysis of a wirebased manufacturing process. In this so called Wire + Arc Additive Manufacturing (WAAM), metal components are arc-welded layer by layer. In addition to the advantages of additive manufacturing, such as the creation of complex geometries in a short time and reduced effort, it is possible to produce large parts using this technology. On the other hand, thermo-mechanically based distortions and residual stresses affect the produced workpieces. In order to investigate and minimize such problems in advance, finite element process simulations are used to search for mitigation strategies. In the first section of this thesis, a literature study is carried out on additive manufacturing and numerical simulation processes. The experimental part of this work deals with a welding process parameter study. In addition to the parameter determination, a representative model is created, which helps to validate and calibrate the simulation results. In addition to the measuring of the stress and temperature profiles during the welding process, residual stress measurements are carried out and the distortion is determined. The obtained data is compared with the simulation study results. In addition, the thermal influence in conjunction with phase transformation during the welding process is discussed on the basis of micrographs. The simulation provides clamping states, geometry dimensions and thermo-metallurgical-mechanical material data which can be compared to the experiments. The recorded temperature profiles are used to calibrate the simulation. The results of this work show that the manufacturing process can be numerically represented well. From the simulations, component properties, such as global deformations and local residual stress states, can be estimated qualitatively. The maximum distortion of the component is up to 3mm in both the simulation and the welding. The temperature values are nearly identical, with maximum differences of 20°C. However, the residual stress results differ significantly by 50-100MPa. The position of the measuring points and the acting temperatures may have influenced these results. Summing up, the developed methods serve as a future reference for the analysis of WAAM production of even more complex geometries.
Translated title of the contributionNumerical and Experimental Analysis of Wire Arc Additive Manufacturing
Original languageGerman
QualificationDipl.-Ing.
Awarding Institution
  • Montanuniversität
Supervisors/Advisors
  • Leitner, Martin, Co-Supervisor (internal)
  • Stoschka, Michael, Supervisor (internal)
Award date12 Apr 2019
Publication statusPublished - 2019

Bibliographical note

no embargo

Keywords

  • Additive Manufacturing
  • Wire Arc Additive Manufacturing
  • Simulation
  • Welding
  • Manufacturing Engineering

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