Study of the Evolution of Distortion During the Powder Bed Fusion Build Process Using a Combined Experimental and Modeling Approach ✶ ✶Reprinted from Additive Manufacturing, Vol 12, Dunbar, Alexander J and Denlinger, Erik R and Gouge, Michael F and Michaleris, Pan, Experimental validation of finite element modeling for laser powder bed fusion deformation, Pages No. 108–120, Copyright (2016), with permission from Elsevier.

Abstract Powder bed fusion (PBF) additive manufacturing has enabled unmatched agile manufacturing of a wide range of products from engine components to medical implants. While high-fidelity finite element modeling and feedback control have been identified key for predicting and engineering part qualities in PBF, existing results in each realm are developed in opposite computational architectures wildly different in time scale. Integrating both realms, this paper builds a first-instance closed-loop simulation framework by utilizing the output signals retrieved from the finite element model (FEM) to directly update the control signals sent to the model. The proposed closed-loop simulation enables testing the limits of advanced controls in PBF and surveying the parameter space fully to generate more predictable part qualities. Along the course of formulating the framework, we verify the FEM by comparing its results with experimental and analytical solutions and then use the FEM to understand the melt-pool evolution induced by the in-layer thermomechanical interactions. From there, we build a repetitive control algorithm to greatly attenuate variations of the melt pool width.

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Erratum: “Transient dynamics and stability of keyhole at threshold in laser powder bed fusion regime investigated by finite element modeling” [J. Laser Appl. 33, 012024 (2021)]

Journal of Laser Applications ◽

10.2351/7.0000371 ◽

2021 ◽

Vol 33 (2) ◽

pp. 029902

Author(s):

Yaasin A. Mayi ◽

Morgan Dal ◽

Patrice Peyre ◽

Michel Bellet ◽

Charlotte Metton ◽

...

Keyword(s):

Finite Element ◽

Finite Element Modeling ◽

Transient Dynamics ◽

Powder Bed Fusion ◽

Laser Powder Bed Fusion ◽

Powder Bed ◽

Element Modeling

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Thermomechanical Model Development and In Situ Experimental Validation of the Laser Powder-Bed Fusion Process ✶ ✶Should note that some content from this chapter was recently published: Denlinger, Erik R., et al. “Thermomechanical model development and in situ experimental validation of the Laser Powder-Bed Fusion Process.” Additive Manufacturing (2017).

Thermo-Mechanical Modeling of Additive Manufacturing ◽

10.1016/b978-0-12-811820-7.00016-1 ◽

2018 ◽

pp. 215-227

Author(s):

Erik R. Denlinger

Keyword(s):

Additive Manufacturing ◽

Experimental Validation ◽

Model Development ◽

Fusion Process ◽

Powder Bed Fusion ◽

Laser Powder Bed Fusion ◽

Thermomechanical Model ◽

Powder Bed

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Analysis of the Porous Structures from Laser Powder Bed Fusion Additive Manufacturing

10.3233/atde210019 ◽

2021 ◽

Author(s):

Chang Jiang Wang ◽

Kevin Hazlehurst ◽

Arun Arjunan ◽

Lida Shen

Keyword(s):

Finite Element ◽

Additive Manufacturing ◽

Bone Ingrowth ◽

Manufacturing Processes ◽

Powder Bed Fusion ◽

Porous Structures ◽

Laser Powder Bed Fusion ◽

Stress Concentrations ◽

Powder Bed ◽

Internal Surfaces

Open and closed porous structures with lattice and honeycomb geometry can be built using laser powder bed fusion additive manufacturing processes. The porous structures can be used to tailor the mechanical properties of a component or provide other functionality, such as for bone ingrowth in medical implants. Porous structures were created and analysed in this paper both physically and using finite element modelling. It was found that the accuracy of the built parts was reasonable and within the manufacturing processes general tolerance of +/- 50 μm. However, it was noticeable that the corners of the square shape pores were naturally filleted by the manufacturing process. The finite element model was developed using ANSYS software, stress concentrations were observed in the porous structures under loading. In addition to this, fragments of the material were present on the internal surfaces of the pores, which were formed from partially melted powder particles.

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Additive manufacturing of 3D structures with non-Newtonian highly viscous fluids: Finite element modeling and experimental validation

Additive Manufacturing ◽

10.1016/j.addma.2016.10.008 ◽

2017 ◽

Vol 13 ◽

pp. 113-123 ◽

Cited By ~ 15

Author(s):

Farzad Liravi ◽

Robin Darleux ◽

Ehsan Toyserkani

Keyword(s):

Finite Element ◽

Additive Manufacturing ◽

Finite Element Modeling ◽

Experimental Validation ◽

Viscous Fluids ◽

3D Structures ◽

Element Modeling

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Finite element modeling of powder bed fusion at part scale by a super-layer deposition method based on level set and mesh adaptation

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4052386 ◽

2021 ◽

pp. 1-26

Author(s):

Yancheng Zhang ◽

Charles-André Gandin ◽

Michel Bellet

Keyword(s):

Finite Element ◽

Finite Element Modeling ◽

Level Set ◽

Mesh Adaptation ◽

Layer By Layer ◽

Powder Bed Fusion ◽

Deposition Method ◽

Powder Bed ◽

Element Modeling ◽

Layer Deposition

Abstract A super-layer deposition method is developed for 3D macroscopic finite element modeling of heat transfer at part scale during the powder bed fusion (PBF) process. The proposed super-layer strategy consists of the deposition of batches of several layers. The main consideration is to deal with the effective heating times and with the inter-layer dwell time in a reasonable way. The material is deposited at once for each super-layer thanks to level-set and mesh adaptation methods, while the energy input is prescribed, either by respecting the layer-by-layer thermal cycle, or in a single thermal load. The level set method is used twice: first to track the interface between gas and the successive super-layers of powder bed and; second to track the interface between the part in construction and the non-exposed powder. To preserve simulation accuracy, adaptive remeshing is used to maintain a fine mesh near the evolving construction front during the process. Simulation results obtained by means of this super-layer method are presented and discussed by comparison with those obtained by layer-by-layer strategy, considered here as a reference. It is shown that, when respecting certain conditions, temperature evolutions and distributions approaching the reference ones can be obtained with significant savings on computation time. Assessment is first performed on simple part, then on a more complex configuration.

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