Abstract

Laser powder bed fusion (LPBF) is a metal additive manufacturing process in which a concentrated laser beam selectively melts successive powder layers to fabricate components. Final part quality is highly sensitive to process parameters such as hatch spacing, powder bed density, laser power, and scanning speed. In this study, a computational fluid dynamics model employing discrete element method has been developed in FLOW-3D to simulate LPBF of Inconel 718. The modeled powder bed incorporates particle size distribution data obtained from scanning electron microscopy and is evaluated for single-layer, single-track deposition over a circular cavity. The model captured melt pool dynamics in terms of width and depth, spattering, and Marangoni convection. Results showed that spattering was limited and melt pool behavior was predominated by the coupled effects of recoil pressure and Marangoni convection. Recoil pressure is identified as a contributing factor to melt pool instabilities associated with spattering behavior, while Marangoni convection influenced melt pool shape and stability. The effect of airflow at various velocities (8–48 cm/s) and exposure times on powder bed stability were also analyzed, revealing that airflow significantly disturbed finer particles at moderate to high velocities. Similarly, low chamber pressures (0.99–0.97 atm) were found to enhance gas velocities and powder displacement over the powder bed.

Department(s)

Mechanical and Aerospace Engineering

Second Department

Materials Science and Engineering

Publication Status

Open Access

Keywords and Phrases

Airflow; Inconel 718; Laser powder bed fusion; Low chamber pressure; Marangoni convection; Spattering

International Standard Serial Number (ISSN)

1433-3015; 0268-3768

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2026 Springer, All rights reserved.

Creative Commons Licensing

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.

Publication Date

01 Jan 2026

Share

 
COinS