In-situ thermographic monitoring and numerical simulations of laser-foil-printing additive manufacturing

• Published in: Virtual and physical prototyping 2025-12, Vol.20 (1)
• Main Authors: Tunay Turk, Tao Liu, Chia-Hung Hung, Richard Billo, Jonghyun Park, Ming C. Leu
• Format: Article
• Language: English
• Subjects: finite element analysis; in situ process monitoring; laser processing; Metal additive manufacturing; sheet feedstock
• ISSN: 1745-2759; 1745-2767
• DOI: 10.1080/17452759.2024.2440609

Laser-foil-printing (LFP) is an additive manufacturing (AM) technique offering advantages over traditional powder-based methods. A deeper understanding of the melt pool dynamics is crucial for optimising process parameters and achieving high-quality builds. This paper presents a combined approach utilising numerical simulations and in-situ thermographic monitoring to investigate the relationship between scanning strategies, melt pool dimensions, and cooling rate in LFP. The numerical simulations are employed to predict melt pool behaviour using a time-dependent thermal finite element analysis (FEA). Results demonstrate that the simulations accurately predict melt pool dimensions, showing strong agreement with experimental data. Simultaneously, real-time melt pool dynamics were monitored through in-situ thermographic techniques, with calibration performed using an empirically known melt pool width for emissivity determination. The continuous line scanning strategy resulted in a gradual increase in cooling rates along the scanning path, while the discrete spot scanning strategy maintained stable cooling rates at each weld spot.