Advancing powder bed fusion-laser beam technology: in-situ layerwise thermal monitoring solutions for thin-wall fabrication

Additive manufacturing (AM) technologies, particularly powder bed fusion-laser beam (PBF-LB/M), offer unique capabilities in producing intricate components directly, leading to streamlined processes, cost reductions, and time savings. However, inherent challenges in AM processes necessitate advanced monitoring systems for fault detection and quality assurance. This study focuses on the development and application of in-situ, layer-by-layer thermal monitoring solutions to detect defects such as localized overheating and inadequate fusion in thin-walled components produced by PBF-LB/M. An optimal setup using an off-axis IR thermal camera was devised to monitor the entire slice during processing. Thermographic data, analyzed using MATLAB, identified thermal parameters indicative of process efficiency and print quality. Micro-tomographic scans on finished products correlated defects with thermographic data. Results showed influences of sample thickness on maximum temperatures, effects of powder bed thickness on process temperatures, and identified geometric distortions in inclined walls due to high thermal stress. Three-dimensional thermograms enabled comprehensive temperature distribution analysis, crucial for quality control and defect detection during construction. Insights from this study advance thermographic analysis for PBF-LB/M processes, providing a foundational framework for future additive manufacturing monitoring and quality control enhancements.