Influence of the particle size distribution on surface quality and mechanical properties in AM steel parts

Emerald - Tập 17 Số 3 - Trang 195-202 - 2011
A.B. Spierings1, N. Herres2, G. Levy1
1INSPIRE – AG für mechatronische Produktionssysteme und Fertigungstechnik, Institute for Rapid Product Development, St Gallen, Switzerland
2NTB Buchs, Buchs, Switzerland

Tóm tắt

PurposeA recent study confirmed that the particle size distribution of a metallic powder material has a major influence on the density of a part produced by selective laser melting (SLM). Although it is possible to get high density values with different powder types, the processing parameters have to be adjusted accordingly, affecting the process productivity. However, the particle size distribution does not only affect the density but also the surface quality and the mechanical properties of the parts. The purpose of this paper is to investigate the effect of three different powder granulations on the resulting part density, surface quality and mechanical properties of the materials produced.Design/methodology/approachThe scan surface quality and mechanical properties of three different particle size distributions and two layer thicknesses of 30 and 45 μm were compared. The scan velocities for the different powder types have been adjusted in order to guarantee a part density≥99.5 per cent.FindingsBy using an optimised powder material, a low surface roughness can be obtained. A subsequent blasting process can further improve the surface roughness for all powder materials used in this study, although this does not change the ranking of the powders with respect to the resulting surface quality. Furthermore, optimised powder granulations lead generally to improved mechanical properties.Practical implicationsThe results of this study indicate that the particle size distribution influences the quality of AM metallic parts, produced by SLM. Therefore, it is recommended that any standardisation initiative like ASTM F42 should develop guidelines for powder materials for AM processes. Furthermore, during production, the granulation changes due to spatters. Appropriate quality systems have to be developed.Originality/valueThe paper clearly shows that the particle size distribution plays an important role regarding density, surface quality and resulting mechanical properties.

Tài liệu tham khảo

Badrosamay, M., Yasa, E., Van Vaerenbergh, J. and Kruth, J.P. (2009), “Improving productivity rate in SLM of commercial steel powders”, paper presented at RAPID 2009 Conference & Exposition, Schaumburg, IL, May. Coremans, A.L.P. (1999), “Laserstrahlsintern von Metallpulver – Prozessmodellierung, Systemtechnik, Eigenschaften laserstrahlgesinterter Metallkörper”, dissertation, University of Erlangen‐Nürnberg, Erlangen. Dimla, D.E., Camilotto, M. and Miani, F. (2005), “Design and optimisation of conformal cooling channels in injection moulding tools”, Journal of Materials Processing Technology, Vol. 164, pp. 1294‐300. German, R.M. (1989), Particle Packing Characteristics, Metal Powder Industries, Princeton, NJ. Karapatis, N.P., Egger, G., Gygax, P.‐E. and Glardon, G. (1999), “Optimization of powder layer density in selective laser sintering”, Proceedings of the 9th Solid Freeform Fabrication Symposium, University of Texas, Austin, TX, USA. Kruth, J.P., Mercelis, P., Van Vaerenbergh, J., Froyen, L. and Rombouts, M. (2005a), “Binding mechanisms in selective laser sintering and selective laser melting”, Rapid Prototyping Journal, Vol. 11, pp. 1355‐2546. Kruth, P.D.I.J.P., Vandenbroucke, B., Van Vaerenbergh, I.J. and Naert, I. (2005b), “Rapid manufacturing of dental prostheses by means of selective laser sintering/melting”, Proceedings of the AFPR, S4, University of Twente, Enschede, The Netherlands. Martienssen, W. and Warlimont, H. (2005), Springer Handbook of Condensed Matter and Materials Data, Springer, Berlin. Over, C. (2003), “Generative Fertigugn von Bauteilen aus Werkzeugstahl X38CrMoV5‐1 und Titan TiAl6V4 mit ‘Selective Laser Melting’”, PhD dissertation, RWTH Aachen University, Aachen. Rehme, O. (2006), “Selective Laser Melting offenzellulärer Struktruen und Charakterisierung ihrer mechanischen Eigenschafte”, WLT Laser‐Summerschool, ed, Institute of Laser and System Technologies, Hamburg University of Technology, Hamburg. Sehrt, J.T. and Witt, G. (2009), “Auswirkungen des anisotropen Gefüges strahlgeschmolzener Bauteile auf mechanische Eigenschaftswerte”, Rapid. Tech., Messe Erfurt AG, Erfurt. Spierings, A.B. and Levy, G. (2009), “Comparison of density of stainless steel 316L parts produced with selective laser melting using different powder grades”, Proceedings of the Annual International Solid Freeform Fabrication Symposium, The University of Texas, Austin, TX, USA, p. 20. Spierings, A.B., Schneider, M. and Eggenberger, R. et al., (2010), “Comparison of density measurement techniques for additive manufactured metallic parts”, Rapid Prototyping (in press).. Wohlers, T. (2005), “Material options: an absence or abundance?”, Time‐Compression Technologies, March/April. Zhang, D. (2004), “Entwicklung des Selective Laser Melting (SLM) für Aluminiumwerkstoffe”, Fakultät für Maschinenwesen, Technische Hochschule Aachen, Aachen.
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Emerald

Tập 17 Số 3

195-202

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