University of Nottingham, UK
In situ monitoring of metal powder bed fusion for defect identification using fringe projection
Additive manufacturing (AM) techniques allow building components on a layer-by-layer basis, with increased precision and efficiency compared to conventional methods. However, AM techniques such as laser-based powder bed fusion (L-PBF), still lack quality assurance due to the appearance of defects during part manufacture. Factors including process parameters, build environment and process stability produce these defects, which jointly influence the integrity of the finished part. In situ monitoring techniques permit to closely inspect the build process and identify emerging defects. However, while defects are originally unwanted, not all of them are detrimental to part microstructure. In this SOTA talk, we present a methodology to discriminate critical/‘killer’ defects from neutral anomalies, using in situ monitoring and topographical analysis. The talk will detail the development of the main monitoring technique, fringe projection, and its deployment inside a commercial L-PBF machine. Thermal imaging will also be discussed as a second monitoring technique used simultaneously. The general pipeline for in situ detection, data analysis and ex-situ testing will be described. The collected data and any detection results will be examined. A summary of the challenges and opportunities for in situ monitoring in AM will be presented.
Afaf Remani is currently pursuing a PhD in Manufacturing Engineering at the University of Nottingham, focusing on the design and development of measurement techniques for in situ monitoring and defect detection in additively manufactured metal parts. Her project is supported by Renishaw plc and is an on-going partnership between the University of Nottingham and Imperial College London. Prior to her PhD, Afaf completed an MSc in Mechanical Engineering, with a specialisation in Manufacturing, at the University of Nottingham and a BSc in General Engineering at Al Akhawayn University (Morocco). She has a solid background in dynamics and mechanics of materials and is a part-time supervisor of undergraduate mechanical engineering laboratories alongside her PhD. Afaf is a collegiate member in the Society of Women Engineers and took part in research and development projects in the United States and Portugal. She co-authored two review papers about in-situ monitoring and defect detection in additive manufacturing, among which one is a high-impact comprehensive review.