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
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.
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Conference: SAMPE 2020 | Virtual Series
Publication Date: 2020/06/01
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