An innovative digital image correlation technique for in-situ process monitoring of composite structures in large scale additive manufacturing. (15th November 2021)

• Record Type: Journal Article
• Authors: Spencer, Ryan; Hassen, Ahmed Arabi; Baba, Justin; Lindahl, John; Love, Lonnie; Kunc, Vlastimil; Babu, Suresh; Vaidya, Uday
• Is Part Of: Composite structures. Volume 276(2021)
• Publication Date: 2021-11-15
• Subjects: Digital image correlation (DIC) -- Additive manufacturing (AM) -- Polymers -- Composites -- Residual Stress; Composite construction -- Periodicals; Composites -- Périodiques; 624.18
• DOI: 10.1016/j.compstruct.2021.114545
• Languages: English
• ISSNs: 0263-8223

Abstract

Highlights: Natural speckle pattern for digital image correlation analysis. Innovative image processing technique enables digital image correlation method. Successfully monitor residual warping in additive manufacturing. Abstract: As additive manufacturing (AM) continues to develop and become a standardized manufacturing method, there will be a continued need to provide in-situ monitoring during the manufacturing of polymer composite printed components. Thermal residual stress is a primary cause of failures such as interlayer disbonds or delamination, micro cracking, and dimensional instability, which can occur during or after the build. This study reports a novel digital image correlation (DIC) adaptation to monitor thermal residual stresses during the entire print process for large-scale AM. In this work, DIC has been investigated (a) by the natural speckle produced by the polymer surface for correlation, (b) to monitor AM build, and (c) to evaluate the effect of thermal residual stress on warpage of the printed component. The natural speckle pattern of the AM material resulted in a respectable 3.57% error compared to the traditional painted speckle pattern of 3.05% error. DIC measured a 190% increase in vertical displacement at the edge of the wall compared to the center, indicating warpage during AM. This work is a step towards a non-intrusive residual stress measuring technique using DIC for large-scale AM.