Abstract
One of the most critical defects in selective laser melting (SLM) is the porosity formation. Optimization of process parameters for reducing the porosity levels to lower than <1% is possible in most of the cases. Susceptibility to porosity formation can be higher for different alloys as function of chemical composition due to higher spark generation and molten pool instabilities. On the other hand, the probability of porosity formation increases in larger components due to an extended processing time. Powder recoater wear, increase in thermal load, and accumulation of particles in the processing chamber become more relevant as the processing time increases. Hence, the use of integrated monitoring and correction strategies becomes crucially important.
In this work, three different correction strategies are discussed for the correction of porosity during the SLM of 18Ni300 maraging steel. The main aim is to develop a possible correction and prevention scheme to be used within a fully monitored SLM process. The 18Ni300 maraging steel is susceptible to high levels of porosity due to the empirically observed melt-pool instabilities as well as high spark and vapor generation. The correction methods consisted of remelting of the defected layer employing different scan strategies namely “double pass,” “soft melting,” and “polishing.” As a preventive strategy, preheating at 170 °C was also evaluated. At an initial stage, all the strategies were tested throughout the part built in order to assess their general capacity in improving the part density. Surface roughness, geometrical error, and material microhardness were also evaluated to assess the impact of the strategies on the other quality aspects. The results indicate the capacity of improving the part density and reduce the part roughness effectively.
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Gong H, Rafi K, Gu H, Starr T, Stucker B (2014) Analysis of defect generation in Ti-6Al-4V parts made using powder bed fusion additive manufacturing processes. Addit Manuf 1:87–98. doi:10.1016/j.addma.2014.08.002
Abdelrahman M, Reutzel EW, Nassar AR, Starr TL (2017) Flaw detection in powder bed fusion using optical imaging. Addit Manuf 15:1–11. doi:10.1016/j.addma.2017.02.001
Neef A, Seyda V, Herzog D, Emmelmann C, Schönleber M, Kogel-Hollacher M (2014) Low coherence interferometry in selective laser melting. Phys Procedia 56:82–89. doi:10.1016/j.phpro.2014.08.100
Everton SK, Hirsch M, Stravroulakis P, Leach RK, Clare AT (2016) Review of in-situ process monitoring and in-situ metrology for metal additive manufacturing. Mater Des 95:431–445. doi:10.1016/j.matdes.2016.01.099
Grasso M, Colosimo BM (2017) Process defects and in situ monitoring methods in metal powder bed fusion: a review. Meas Sci Technol 28:44005. doi:10.1088/1361-6501/aa5c4f
Kasperovich G, Haubrich J, Gussone J, Requena G (2016) Correlation between porosity and processing parameters in TiAl6V4 produced by selective laser melting. Mater Des 105:160–170. doi:10.1016/j.matdes.2016.05.070
Kamath C, El-dasher B, Gallegos GF, King WE, Sisto A (2014) Density of additively-manufactured, 316L SS parts using laser powder-bed fusion at powers up to 400 W. Int J Adv Manuf Technol:65–78. doi:10.1007/s00170-014-5954-9
Aboulkhair NT, Everitt NM, Ashcroft I, Tuck C (2014) Reducing porosity in AlSi10Mg parts processed by selective laser melting. Addit Manuf 1:77–86. doi:10.1016/j.addma.2014.08.001
Senthilkumaran K, Pandey PM, Rao PVM (2009) Influence of building strategies on the accuracy of parts in selective laser sintering. Mater Des 30:2946–2954. doi:10.1016/j.matdes.2009.01.009
Bouwer S (2016) Leveraging geometry optimization tools to reduce component weight, development cost, and design schedule Philadelphia, PA. AHS Int 72nd Annu Forum 1–20
Cloots M, Spierings AB, Wegener K (2013) Assessing new support minimizing strategies for the additive manufacturing technology SLM. Int Solid Free Fabr Symp An Addit Manuf Conf August 12-14 2013:131–9. doi:10.1017/CBO9781107415324.004
Calignano F (2014) Design optimization of supports for overhanging structures in aluminum and titanium alloys by selective laser melting. Mater Des 64:203–213. doi:10.1016/j.matdes.2014.07.043
Yadroitsev I, Krakhmalev P, Yadroitsava I, Johansson S, Smurov I (2013) Energy input effect on morphology and microstructure of selective laser melting single track from metallic powder. J Mater Process Technol 213:606–613. doi:10.1016/j.jmatprotec.2012.11.014
Buchbinder D, Meiners W, Pirch N, Wissenbach K, Schrage J (2014) Investigation on reducing distortion by preheating during manufacture of aluminum components using selective laser melting. J Laser Appl 26:12004. doi:10.2351/1.4828755
Zhou S, Huang Y, Zeng X, Hu Q (2008) Microstructure characteristics of Ni-based WC composite coatings by laser induction hybrid rapid cladding. Mater Sci Eng A 480:564–572. doi:10.1016/j.msea.2007.07.058
Zhou S, Zeng X, Hu Q, Huang Y (2008) Analysis of crack behavior for Ni-based WC composite coatings by laser cladding and crack-free realization. Appl Surf Sci 255:1646–1653. doi:10.1016/j.apsusc.2008.04.003
Zarini S, Previtali B, Vedani M, Rovatti L (2014) Cracks susceptibility elimination in fiber laser cladding of Ni-based alloy with addition of tungsten carbides. Proc. ASME 2014 12th Bienn. Conf. Eng. Syst. Des. Anal. ESDA2014, p. ESDA2014–20623
Yasa E, Kruth JP (2010) Investigation of laser and process parameters for selective laser erosion. Precis Eng 34:101–112. doi:10.1016/j.precisioneng.2009.04.001
MC Machinery Systems Inc (n.d.) Lumex Avance 25 https://www.mcmachinery.com/products-and-solutions/lumex-avance/ (accessed March 2, 2017)
Sodick Co Ltd (n.d.) OPM350L http://www.sodick.jp/product/tool/metal_3d_printer/index.html (accessed March 2, 2017)
Kruth J-P, Yasa E, Deckers J (2008) Roughness improvement in selective laser melting. Proc 3rd Int Conf Polym Mould Innov 170–83.
Vaithilingam J, Goodridge RD, Hague RJM, Christie SDR, Edmondson S (2016) The effect of laser remelting on the surface chemistry of Ti6al4V components fabricated by selective laser melting. J Mater Process Technol 232:1–8. doi:10.1016/j.jmatprotec.2016.01.022
Kruth J, Badrossamay M, Yasa E, Deckers J, Thijs L, Van Humbeeck J (2010) Part and material properties in selective laser melting of metals. 16th Int Symp Electromachining 1–12
Yasa E, Kempen K, Kruth J (2010) Microstructure and mechanical properties of Maraging Steel 300 after selective laser melting. Proc 21st Int Solid Free Fabr Symp 383–96
Jägle EA, Choi P-P, Van Humbeeck J, Raabe D (2014) Precipitation and austenite reversion behavior of a maraging steel produced by selective laser melting. J Mater Res 29:2072. doi:10.1557/jmr.2014.204
Demir AG, Colombo P, Previtali B (2017) From pulsed to continuous wave emission in SLM with contemporary fiber laser sources: effect of temporal and spatial pulse overlap in part quality. Int J Adv Manuf Technol 91:2701–2714. doi:10.1007/s00170-016-9948-7
Zhou X, Liu X, Zhang D, Shen Z, Liu W (2015) Balling phenomena in selective laser melted tungsten. J Mater Process Technol 222:33–42. doi:10.1016/j.jmatprotec.2015.02.032
Lamikiz A, Sánchez JA, López de Lacalle LN, Arana JL (2007) Laser polishing of parts built up by selective laser sintering. Int J Mach Tools Manuf 47:2040–2050. doi:10.1016/j.ijmachtools.2007.01.013
De Giorgi C, Furlan V, Demir AG, Tallarita E, Candiani G, Previtali B (2017) Laser micropolishing of AISI 304 stainless steel surfaces for cleanability and bacteria removal capability. Appl Surf Sci 406:199–211. doi:10.1016/j.apsusc.2017.02.083
Qiu C, Panwisawas C, Ward M, Basoalto HC, Brooks JW, Attallah MM (2015) On the role of melt flow into the surface structure and porosity development during selective laser melting. Acta Mater 96:72–79. doi:10.1016/j.actamat.2015.06.004
Casati R, Lemke JN, Tuissi A, Vedani M (2016) Aging behaviour and mechanical performance of 18-Ni 300 steel processed by selective laser melting. Metals (Basel) 6. doi:10.3390/met6090218
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Demir, A.G., Previtali, B. Investigation of remelting and preheating in SLM of 18Ni300 maraging steel as corrective and preventive measures for porosity reduction. Int J Adv Manuf Technol 93, 2697–2709 (2017). https://doi.org/10.1007/s00170-017-0697-z
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DOI: https://doi.org/10.1007/s00170-017-0697-z