A thermal finite element model with efficient computation of surface heat fluxes for directed-energy deposition process and application to laser metal deposition of IN718

Dortkasli K., Isik M., Demir E.

Journal of Manufacturing Processes, vol.79, pp.369-382, 2022 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 79
  • Publication Date: 2022
  • Doi Number: 10.1016/j.jmapro.2022.04.049
  • Journal Name: Journal of Manufacturing Processes
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, ABI/INFORM, Compendex, INSPEC
  • Page Numbers: pp.369-382
  • Keywords: Directed-energy deposition, Thermal process simulation, FEM, IN-718, PREDICT RESIDUAL-STRESSES, INCONEL 718, MICROSTRUCTURE EVOLUTION, SCAN STRATEGY, DISTORTION, FLOW, SOLIDIFICATION, MICROHARDNESS, INPUT, STEEL
  • Bursa Uludag University Affiliated: Yes

Abstract

© 2022 The Society of Manufacturing EngineersIn this study, a numerically efficient thermal finite element process model is developed to predict the melt-pool characteristics of directed-energy deposition (DED) process. The model uses a new technique to compute the effective surface heat loss terms in the form of a volumetric heat sink term in order to avoid the redefinition of surface heat fluxes from the free-surfaces after addition of every layer. In addition, thermal model incorporated the heat losses due to evaporation and Marangoni effect by changing the conductivity at the liquid state. The melt pool dimensions of IN718 were experimentally measured by in-situ thermal monitoring and by ex-situ optical microscopy of the cross-sections of the deposited tracks. The proposed model accurately predicts the experimental melt-pool dimensions of single-track and multi-layer depositions over the range of process parameters.