21 - Identifying Laser Beam Melting (LBM) process window for thin walls by enriching design of experiments with analytical physical models

Abstract

Design of lightweight structures usually relies on slender elements and architectured materials that maximize specific properties. In additive manufacturing, standard process parameters are not necessarily optimized with regards to thin parts (<400 µm), like skins and struts (Figure 1a). The purpose of the present work is to explore the parameter space of Laser Beam Melting process for a given material (AlSi7Mg06) and to define process windows for skins and struts compliant with some performance criteria, including mechanical properties. Initially, the exploration strategy relied on machine learning methods to minimize characterization efforts and assess robustness of the results. Since, the approach has been enhanced using analytical physical models from the literature. Predictive process maps are constructed from criteria for the occurrence of defects [1] or thermal models for melt pool size assessment [2] (Figure 1b). With physical considerations, relevant metrics implying both material properties and process parameters are constructed [3] while dimensional analyses [4] anticipates trends. Single-bead thin walls are characterized to challenge the predictive character of the models despite their simplicity. Their interest for rationalizing designs of experiment or transferring present result to large-scale production machines is discussed. Figure 1. (a) Single-bead thin walls in AS7G06. (b) Predictive process maps constructed from simple physical models (red: keyhole porosity, gray: balling porosity, green: dense, blue: lack of fusion). References: [1] P. Promoppatum, S.-C. Yao, Int J Adv Manuf Technol 103 (2019) 1185–1198. [2] A.M. Rubenchik, W.E. King, S.S. Wu, Journal of Materials Processing Technology 257 (2018) 234–243. [3] D.B. Hann, J. Iammi, J. Folkes, in: S. Hinduja, L. Li (Eds.), Proceedings of the 36th International MATADOR Conference, Springer, London, 2010, pp. 275–278. [4] A. Großmann, J. Felger, T. Frölich, J. Gosmann, C. Mittelstedt, Materials & Design 181 (2019) 108054.

Speaker

Clément Ernould

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IRT Saint Exupéry, Toulouse, France

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Conference

21 - Identifying Laser Beam Melting (LBM) process window for thin walls by enriching design of experiments with analytical physical models

Date/Time

21/03/2024

11:05 am -11:25 am

Location

Room 6