A systematic study and framework of fringe projection profilometry with improved measurement performance for in-situ LPBF process monitoring

Journal Article · 29 January 2022 · Measurement

DOI: https://doi.org/10.1016/j.measurement.2022.110796 · OSTI ID:1977428

Zhang, Haolin ^[1]; Vallabh, Chaitanya Prasad ^[2]; Xiong, Yubo ^[2]; Zhao, Xiayun ^[2]

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1. Univ. of Pittsburgh, PA (United States); OSTI
2. Univ. of Pittsburgh, PA (United States)

Fringe Projection Profilometry (FPP) is a cost-effective and non-invasive technology that has been shown to measure finer features. Here, in this work, we developed an in-situ FPP method to measure the dynamic topography of powder bed and printed layer during Laser Powder Bed Fusion (LPBF) additive manufacturing (AM) process. A systematic study towards developing a comprehensive framework of LPBF-specific FPP is demonstrated to enhance and evaluate the performance of applying FPP for in-situ LPBF monitoring, including 1) a modified sensor model with localized correction; 2) improved phase unwrapping with FFT filtering 3) quantitative uncertainty analysis; and 4) experimental validation with ex-situ characterization. The developed LPBF-specific FPP system and methods are implemented on a commercial LPBF-AM machine, achieving better accuracy, more robustness, and increased field of view while maintaining sufficient measurement range and decent resolution, in contrast to literature methods. The established FPP framework will facilitate the development of closed-loop control strategies for advancing LPBF based AM.

• Research Organization: Univ. of Pittsburgh, PA (United States)
• Sponsoring Organization: USDOE Office of Fossil Energy (FE)
• Grant/Contract Number: FE0031774
• OSTI ID: 1977428
• Journal Information: Measurement, Journal Name: Measurement Vol. 191; ISSN 0263-2241
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English