Title: Development of Intermittent Layer Height Control Using Line Scanning for Successive Toolpath Adaption in Laser Material Deposition

Authors: Jan Bremer, Tim Fleischhauer, Andres Gasser and Johannes Henrich Schleifenbaum

DOI: 10.33599/nasampe/s.20.0232

Abstract: Laser Material Deposition (LMD), also known as Directed Energy Deposition (DED), is an additive manufacturing (AM) technology used in repair and manufacturing applications of high-value components. It is commonly used in industries such as aerospace, tooling and turbomachinery. The ability to produce near-net-shape parts results in low material losses and can lead to reduction of production costs and lead times compared to conventional machining processes. In hybrid manufacturing, LMD is used together with conventional processes to exploit both technologies’ benefits for production of large parts with complex structures. Increasing stability and geometric accuracy of LMD processes is key enabler for further expansion of applications of this manufacturing technology. Current approaches focus on parameter studies, development of predictive modeling as well as closed-loop control. This work proposes a novel approach for component geometry control in LMD. This approach is based on an intermittent geometry control. LMD builds are split into separate sections. After depositing a section or block, a laser line scanner is utilized to measure the detected block geometry in the form of a point cloud. An algorithm is developed that calculates local height deviations from target geometry and adjusts the feed rate along the tool center point (TCP) path. Experiments are conducted in order to establish control parameters such as reference distance between adjacent support points along the TCP path (minimum and maximum feed rate increment) and functional relation between layer height and feed rate. Thus, dependence of layer height with respect to absolute part height is investigated.

References: [1] D. Konitzer, S. Duclos, and T. Rockstroh, “Materials for sustainable turbine engine development,” MRS Bull., vol. 37, no. 4, pp. 383–387, 2012. [2] R. Dehoff et al., “Case Study: Additive Manufacturing of Aerospace Brackets,” Advanced Materials and Processes, vol. 171, 2013. [3] J. M. Flynn, A. Shokrani, S. T. Newman, and V. Dhokia, “Hybrid additive and subtractive machine tools – Research and industrial developments,” International Journal of Machine Tools and Manufacture, vol. 101, pp. 79–101, 2016. [4] J. I. Arrizubieta, M. Cortina, J. E. Ruiz, and A. Lamikiz, “Combination of Laser Material Deposition and Laser Surface Processes for the Holistic Manufacture of Inconel 718 Components,” (eng), Materials (Basel, Switzerland), vol. 11, no. 7, 2018. [5] F. Klocke, Fertigungsverfahren 5. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. [6] I. Garmendia, J. Pujana, A. Lamikiz, J. Flores, and M. Madarieta, “Development of an Intra-Layer Adaptive Toolpath Generation Control Procedure in the Laser Metal Wire Deposition Process,” (eng), Materials (Basel, Switzerland), vol. 12, no. 3, 2019. [7] I. Garmendia, J. Leunda, J. Pujana, and A. Lamikiz, “In-process height control during laser metal deposition based on structured light 3D scanning,” Procedia CIRP, vol. 68, pp. 375–380, 2018. [8] I. Garmendia, J. Pujana, A. Lamikiz, M. Madarieta, and J. Leunda, “Structured light-based height control for laser metal deposition,” Journal of Manufacturing Processes, vol. 42, pp. 20–27, 2019. [9] L. Song, V. Bagavath-Singh, B. Dutta, and J. Mazumder, “Control of melt pool temperature and deposition height during direct metal deposition process,” Int J Adv Manuf Technol, vol. 58, no. 1-4, pp. 247–256, 2012. [10] M. Zeinali and A. Khajepour, “Height Control in Laser Cladding Using Adaptive Sliding Mode Technique: Theory and Experiment,” Int J Adv Manuf Technol, vol. 132, no. 4, p. 501, 2010. [11] A. Heralić, A.-K. Christiansson, and B. Lennartson, “Height control of laser metal-wire deposition based on iterative learning control and 3D scanning,” Optics and Lasers in Engineering, vol. 50, no. 9, pp. 1230–1241, 2012. [12] H. Qi, M. Azer, and P. Singh, “Adaptive toolpath deposition method for laser net shape manufacturing and repair of turbine compressor airfoils,” Int J Adv Manuf Technol, vol. 48, no. 1-4, pp. 121–131, 2010. [13] D. Hu and R. Kovacevic, “Sensing, modeling and control for laser-based additive manufacturing,” International Journal of Machine Tools and Manufacture, vol. 43, no. 1, pp. 51–60, 2003. [14] M. Buhr, J. Weber, J.-P. Wenzl, M. Möller, and C. Emmelmann, “Influences of process conditions on stability of sensor controlled robot-based laser metal deposition,” Procedia CIRP, vol. 74, pp. 149–153, 2018. [15] M. A. Fischler and R. C. Bolles, “Random Sample Consensus: A Paradigm for Model Fitting with Applications to Image Analysis and Automated Cartography,” Communications of the ACM, vol. 24, no. 6, 381-395, 1981.

Conference: SAMPE 2020 | Virtual Series

Publication Date: 2020/06/01

SKU: TP20-0000000232

Pages: 15

Price: FREE