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SUPPORT-FREE METAL ADDITIVE MANUFACTURING: A STRUCTURED REVIEW ON THE STATE OF THE ART IN ACADEMIA AND INDUSTRY

Published online by Cambridge University Press:  27 July 2021

Sebastian Weber*
Affiliation:
University of the Bundeswehr Munich; Bundeswehr Research Institute for Materials, Fuels and Lubricants (WIWeB)
Joaquin Montero
Affiliation:
University of the Bundeswehr Munich; Bundeswehr Research Institute for Materials, Fuels and Lubricants (WIWeB)
Matthias Bleckmann
Affiliation:
Bundeswehr Research Institute for Materials, Fuels and Lubricants (WIWeB)
Kristin Paetzold
Affiliation:
University of the Bundeswehr Munich;
*
Weber, Sebastian, Bundeswehr University Munich, Department of Aerospace Engineering, Germany, s.weber@unibw.de

Abstract

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Especially in the Laser Powder Bed Fusion (L-PBF) technology for metals, current manufacturing systems require the use of support structure to withstand recoater forces and lower thermal induced stresses. These support structures set limitations on the design freedom and affect the surface quality, part cost and lead-time in an undesirable manner. Complex parts, which were not possible with conventional manufacturing methods, can be produced without these limitations. While some companies claim to print parts with horizontal overhangs without the use of support structure, academic research seems to deal with these limitations by defining design guidelines rather than eliminating them. In order to highlight the discrepancies between academia and industry, a structured review is presented. As result, severe differences in knowledge were discovered, which might emerge from the use of unconstrained cutting-edge systems in industry. Eventually support-free L-PBF is not yet fully developed, but the use of support structure can be drastically reduced by optimizing the build process.

Type
Article
Creative Commons
Creative Common License - CCCreative Common License - BYCreative Common License - NCCreative Common License - ND
This is an Open Access article, distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives licence (http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is unaltered and is properly cited. The written permission of Cambridge University Press must be obtained for commercial re-use or in order to create a derivative work.
Copyright
The Author(s), 2021. Published by Cambridge University Press

References

3D Systems. (2018), “DMP Flex 100”, 3D Systems, available at: https://www.3dsystems.com/3d-printers/dmp-flex-100 (accessed 2 November 2020).Google Scholar
Atzeni, E. and Salmi, A. (2015), “Study on unsupported overhangs of AlSi10Mg parts processed by Direct Metal Laser Sintering (DMLS)”, Journal of Manufacturing Processes, Vol. 20, pp. 500506.CrossRefGoogle Scholar
Bagg, S.D., Sochalski-Kolbus, L.M. and Bunn, J.R. (2016), “The Effect of Laser Scan Strategy on Distortion and Residual Stresses of Arches made with Selective Laser Melting”, NASA Technical Reports, presented at the American Society of Precision Engineering (ASPE) 2016 Summer Topical Meeting: Dimensional Accuracy and Surface Finish in Additive Manufacturing, Huntsville.Google Scholar
Boissonneault, T. (2019), “VELO3D: breaking barriers in metal AM with support-free 3D printing”, 3D Printing Media Network, 3 July, available at: https://www.3dprintingmedia.network/velo3d-metal-am-support-free-interview/ (accessed 2 November 2020).Google Scholar
Buller, B., Milshtein, E. and Seelinger, S. (2016), “Apparatuses, systems and methods for three-dimensional printing. U.S. Patent No. 9,346,127 B2”, Santa Clara, CA, 24 May.Google Scholar
Chen, H., Gu, D., Xiong, J. and Xia, M. (2017), “Improving additive manufacturing processability of hard-to-process overhanging structure by selective laser melting”, Journal of Materials Processing Technology, Vol. 250, pp. 99108.CrossRefGoogle Scholar
Chivel, Y. (2013), “Investigations of the selective laser melting of the overhang layers”, in Veiko, V.P. and Vartanyan, T.A. (Eds.), presented at the Fundamentals of Laser Assisted Micro- and Nanotechnologies 2013, St. Petersburg, Russian Federation, available at:https://doi.org/10.1117/12.2052541.Google Scholar
Cloots, M., Spierings, A. and Wegener, K. (2013), “Assessing new support minimizing strategies for the additive manufacturing technology SLM”, Solid Freeform Fabrication Symposium (SFF), Austin, TX, pp. 1214.Google Scholar
Cloots, M., Zumofen, L., Spierings, A.B., Kirchheim, A. and Wegener, K. (2017), “Approaches to minimize overhang angles of SLM parts”, Rapid Prototyping Journal, Vol. 23 No. 2, pp. 362369.CrossRefGoogle Scholar
Cooper, K., Steele, P., Cheng, B. and Chou, K. (2017), “Contact-Free Support Structures for Part Overhangs in Powder-Bed Metal Additive Manufacturing”, Inventions, Vol. 3 No. 1, available at:https://doi.org/10.3390/inventions3010002.CrossRefGoogle Scholar
DePond, P.J., Guss, G., Ly, S., Calta, N.P., Deane, D., Khairallah, S. and Matthews, M.J. (2018), “In situ measurements of layer roughness during laser powder bed fusion additive manufacturing using low coherence scanning interferometry”, Materials & Design, Elsevier, Vol. 154, pp. 347359.CrossRefGoogle Scholar
Grimm, T. (2020), “The Business Impact of a Support-Less Process for Metal Additive Manufacturing”, Campbell, CA, 30 January.Google Scholar
Hall, H. (2020), “Support structures: the need, impact, and elimination strategies”, R&Dworld, 31 January, available at: https://www.rdworldonline.com/support-structures-the-need-impact-and-elimination-strategies/ (accessed 2 November 2020).Google Scholar
Hevner, A.R., March, S.T., Park, J. and Ram, S. (2004), “Design science in information systems research”, MIS Quarterly, JSTOR, pp. 75105.CrossRefGoogle Scholar
Hong, R., Zhang, L., Lifton, J., Daynes, S., Wei, J., Feih, S. and Lu, W.F. (2020), “Artificial neural network-based geometry compensation to improve the printing accuracy of selective laser melting fabricated sub-millimetre overhang trusses”, Additive Manufacturing, available at:https://doi.org/10.1016/j.addma.2020.101594.CrossRefGoogle Scholar
Hussein, A., Hao, L., Yan, C. and Everson, R. (2013), “Finite element simulation of the temperature and stress fields in single layers built without-support in selective laser melting”, Materials & Design (1980-2015), Vol. 52, pp. 638647.Google Scholar
Kranz, J., Herzog, D. and Emmelmann, C. (2015), “Design guidelines for laser additive manufacturing of lightweight structures in TiAl6V4”, Journal of Laser Applications, Vol. 27 No. S1, available at:https://doi.org/10.2351/1.4885235.CrossRefGoogle Scholar
Langelaar, M. (2018), “Combined optimization of part topology, support structure layout and build orientation for additive manufacturing”, Structural and Multidisciplinary Optimization, Vol. 57 No. 5, available at:https://doi.org/10.1007/s00158-017-1877-z.CrossRefGoogle Scholar
Le, K.Q., Wong, C.H., Chua, K.H.G., Tang, C. and Du, H. (2020), “Discontinuity of overhanging melt track in selective laser melting process”, International Journal of Heat and Mass Transfer, Vol. 162, available at:https://doi.org/10.1016/j.ijheatmasstransfer.2020.120284.CrossRefGoogle Scholar
Li, Z., Zhang, D.Z., Dong, P. and Kucukkoc, I. (2017), “A lightweight and support-free design method for selective laser melting”, The International Journal of Advanced Manufacturing Technology, Vol. 90 No. 9-12, pp. 29432953.CrossRefGoogle Scholar
Mertens, R., Clijsters, S., Kempen, K. and Kruth, J.-P. (2014), “Optimization of Scan Strategies in Selective Laser Melting of Aluminum Parts With Downfacing Areas”, Journal of Manufacturing Science and Engineering, Vol. 136 No. 6, available at:https://doi.org/10.1115/1.4028620.CrossRefGoogle Scholar
Miller, G. (2020), “How to Build the Better Fuel Tank, Fast!”, presented at the VeloVirtual Series, 4 November.Google Scholar
Mohanty, S. and Hattel, J.H. (2016), “Improving accuracy of overhanging structures for selective laser melting through reliability characterization of single track formation on thick powder beds”, in Gu, B., Helvajian, H. and Piqué, A. (Eds.), presented at the SPIE LASE, San Francisco, California, United States, available at:https://doi.org/10.1117/12.2212621.Google Scholar
Nimelä, V. (2020), “Together we exceed any limitations of 3D printing - Delva”, Delva - 3D-Tulosteita Kovaan Käyttöön, 10 November, available at: https://delva.fi/en/news/together-we-exceed-any-limitations-of-3d-printing/ (accessed 17 November 2020).Google Scholar
Paggi, U., Sinico, M., Thijs, L., Dewulf, W. and van Hooreweder, B. (2019), “Improving the dimensional accuracy of downfacing surfaces of additively manufactured parts”, Proceedings of the Special Interest Group Meeting on Advancing Precision in Additive Manufacturing, presented at the 2019 euspen and ASPE Special Interest Group Meeting: Advancing Precision in Additive Manufacturing, pp. 3538.Google Scholar
Patterson, A.E., Messimer, S.L. and Farrington, P.A. (2017), “Overhanging Features and the SLM/DMLS Residual Stresses Problem: Review and Future Research Need”, Technologies, Vol. 5 No. 2, p. 15.CrossRefGoogle Scholar
Protolabs. (2018), “How to Design and Manufacture Metal 3D-Printed Parts”, Protolabs, available at: https://www.protolabs.com/resources/design-tips/how-to-design-and-manufacture-metal-3d-printed-parts/ (accessed 2 November 2020).Google Scholar
Saunders, M. (2017), “Can you build AM parts without supports?”, available at: https://www.renishaw.com/en/can-you-build-am-parts-without-supports--43421 (accessed 2 November 2020).Google Scholar
Thompson, M.K., Moroni, G., Vaneker, T., Fadel, G., Campbell, R.I., Gibson, I., Bernard, A., et al. (2016), “Design for Additive Manufacturing: Trends, opportunities, considerations, and constraints”, CIRP Annals, Vol. 65 No. 2, pp. 737760.CrossRefGoogle Scholar
Valdivieso, C. (2020), “What are the business benefits of support-less metal additive manufacturing?”, 3Dnatives, 26 February, available at: https://www.3dnatives.com/en/support-less-metal-additive-manufacturing-260220204/ (accessed 2 November 2020).Google Scholar
Velo3D. (2020), “Sapphire Printer - Product Brief”, October, available at: https://www.velo3d.com/wp-content/uploads/2020/10/PB-Sapphire-v2_0-weightier.pdf (accessed 17 November 2020).Google Scholar
Vora, P., Mumtaz, K., Todd, I. and Hopkinson, N. (2015), “AlSi12 in-situ alloy formation and residual stress reduction using anchorless selective laser melting”, Additive Manufacturing, Vol. 7, pp. 1219.CrossRefGoogle Scholar
Wang, D., Yang, Y., Yi, Z. and Su, X. (2013), “Research on the fabricating quality optimization of the overhanging surface in SLM process”, The International Journal of Advanced Manufacturing Technology, Vol. 65 No. 9-12, pp. 14711484.CrossRefGoogle Scholar
Wang, Y., Gao, J. and Kang, Z. (2018), “Level set-based topology optimization with overhang constraint: Towards support-free additive manufacturing”, Computer Methods in Applied Mechanics and Engineering, Vol. 339, pp. 591614.CrossRefGoogle Scholar
Wohlers, T., Campbell, R.I., Diegel, O., Huff, R. and Kowen, J. (2020), Wohlers Report 2020 3D Printing and Additive Manufacturing State of the Industry.Google Scholar
Wohlfart, M. (2019a), “Can you Build a 100 mm Support-free Horizontal Disk?”, Linkedin, 11 March, available at: https://www.linkedin.com/pulse/can-you-build-100-mm-support-free-horizontal-disk-michael-wohlfart/ (accessed 2 November 2020).Google Scholar
Wohlfart, M. (2019b), “Building without support? Possibilities and limitations”, Linkedin, 12 November, available at: https://www.linkedin.com/pulse/building-without-support-possibilities-limitations-michael-wohlfart/ (accessed 2 November 2020).Google Scholar
Wohlfart, M. (2020), “10° unsupported overhang in 316L with a hard recoater?”, Linkedin, 28 September, available at: https://www.linkedin.com/posts/michael-wohlfart_eos-m290-teamwork-activity-6727155259044569088-KYwj (accessed 2 November 2020).Google Scholar
Zhang, K., Fu, G., Zhang, P., Ma, Z., Mao, Z. and Zhang, D.Z. (2018), “Study on the Geometric Design of Supports for Overhanging Structures Fabricated by Selective Laser Melting”, Materials, Vol. 12 No. 1, available at:https://doi.org/10.3390/ma12010027.CrossRefGoogle Scholar
Zhang, X., Wang, J., Kang, J., Rong, Y., Duan, G., Wu, P. and Zheng, L. (2020), “The dynamic arch bending mechanism of flat bridge structure of AlSi10Mg during SLM process”, Materials & Design, Vol. 188, available at:https://doi.org/10.1016/j.matdes.2020.108469.CrossRefGoogle Scholar