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The role of particle size on the laser sintering of iron powder

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Abstract

The effects of powder particle size on the densification and microstructure of iron powder in the direct laser sintering process were investigated. Iron powders with particle sizes ranging from 10 to 200 µm were used. It was found that the sintered density increases as the laser energy input is increased. There is, however, a saturation level at which higher density cannot be obtained even at very intensive energy input. This saturation density increases as the size of the iron particles decreases. Meanwhile fine powders with narrow particle size distributions have a tendency toward agglomeration, and coarse powders with broad particle size distributions have a tendency toward segregation, both of them resulting in lower attainable density. In order to investigate the role of particle size, a “densification coefficient (K)” was defined and used. This coefficient depends on the particle size and the oxygen content of iron powder. The results of this investigation demonstrate that the presence of oxygen significantly influences the densification and pore morphology of laser-sintered iron. At higher oxygen concentrations, the iron melt pool is solidified to agglomerates, and formation of pores with orientation toward the building direction is more likely to occur. When the oxygen concentration is kept constant, the densification coefficient decreases with decreasing the particle size, meaning the densification kinetics enhances. This article presents the role of powder characteristics and the processing parameters in the laser sintering of iron powder as a model material. The mechanism of particle bonding and microstructural features of laser-sintered parts are addressed.

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Abbreviations

C 1, C 2 :

constants in Eq. [2]

D :

densification, Eq. [4]

d :

thickness of layer, mm

h :

scan line spacing, mm

K :

densification coefficient, Eqs. [2] and [5]

MPS:

mean particle size, µm

P :

laser power, W

T :

temperature

ν :

scan rate, mm/s

ρ bed :

density of powder bed, pct theoretical

ρ ls :

density of laser-sintered specimen, pct theoretical

ρ st :

saturation density, pct theoretical

ρ tab :

tap density, pct theoretical

γ :

surface tension, Nm s−1

ω :

laser energy input per volume of sintered specimen, kJ/mm3

ϕ :

agglomeration factor, ρ bed/ρ tap

References

  1. P.T. Pham and S. Dimov: Rapid Manufacturing: The Technologies and Applications of Rapid Prototyping and Rapid Tooling, Springer-Verlag, London, United Kingdom, 2001.

    Google Scholar 

  2. R. Irving: Int. J. Powder Metall., 2000, vol. 36 (4), pp. 69–71.

    CAS  Google Scholar 

  3. A. Gebhardt: Rapid Prototyping: Tools for Rapid Product Development, Carl Hanser Verlag, Munich, 1996.

    Google Scholar 

  4. T. Wohlers: CATIA Solution Mag., 2000, Jan–Feb.

  5. R.J.M. Hangue and P.E. Reeves: RAPRA Review Reports, RAPRA Technology, Shrewsbury, United Kingdom, 2000, vol. 10 (9).

  6. T. Wohlers: Rapid Prototyping and Tooling State of the Industry: Worldwide Progress Report, Wohlers Associates, Inc., Fort Collins, CO, 2000.

    Google Scholar 

  7. D. Atkinson: Rapid Prototyping and Tooling: A Practical Guide, Strategy Publications Ltd., Welwyn Garden City, Herts, UK, 1997.

    Google Scholar 

  8. F. Klocke, T. Celiker, and Y.A. Song: Rapid Prototyping J., 1995, vol. 1 (3), pp. 32–42.

    Article  Google Scholar 

  9. G.B. Prabhu and D.L. Bourell: Proc. Solid Freeform Fabrication Symp., The University of Texas at Austin, Austin, TX, 1993, pp. 317–24.

    Google Scholar 

  10. M. Greulich, H.D. Kunze, M. Greul, and T. Pintat: Rapid Prototyping & Tooling Newsletter, Danish Technology Institute, Aarhus, Denmark, 1996, vol. 9, pp. 14–15.

    Google Scholar 

  11. C. Hauser, T.H.C. Childs, K.W. Dalgarno, and R.B. Eane: Proc. Solid Freeform Fabrication Symp., The University of Texas at Austin, Austin, TX, 1999, pp. 265–72.

    Google Scholar 

  12. C. Hauser, T.H.C. Childs, and K.W. Dalgarno, Proc. Solid Freeform Fabrication Symp., The University of Texas at Austin, Austin, 1999, pp. 273–80.

    Google Scholar 

  13. H.J. Niu and I.T.H. Chang: Scripta Mater., 1999, vol. 41 (1), pp. 25–30.

    Article  CAS  Google Scholar 

  14. H.J. Niu and I.T.H. Chang: Scripta Mater., 1998, vol. 39 (1), pp. 67–72.

    Article  CAS  Google Scholar 

  15. H.J. Niu and I.T.H. Chang: Scripta Mater., 1999, vol. 41 (1), pp. 1229–34.

    Article  CAS  Google Scholar 

  16. S. Das, T.P. Fuesting, G. Danyo, L.E. Brown, J.J. Beaman, and D.L. Bourell: Mater. Design, 2000, vol. 21, pp. 63–73.

    Article  CAS  Google Scholar 

  17. T. Laoui, L. Froyen, and J.P. Kruth: Proc. PM World Congr., Granada, EPMA, Shrewsbury, UK, 18–22 October, Granada, Spain, 1998, vol. 5, pp. 394–99.

  18. F. Petzoldt, M. Greul, and H. Löffler: Advances in Powder Metallurgy & Particular Materials, MPIF, Princeton, NJ, 1999, vol. 2 (5), pp. 71–76.

    Google Scholar 

  19. H. Pohl: EPMA Short Course on Sintering Science and Practice, Bremen, Sept. 1999.

  20. W. Meiners, C. Over, K. Wissenbach, and R. Poprawe, Proc. Solid Freeform Fabrication Symp., The University of Texas at Austin, Austin, TX, 1999, pp. 655–61.

    Google Scholar 

  21. K.W. Dalgarno and C.S. Wright: Powder Met. Progr., 2001, vol. 1 (1), pp. 70–79.

    CAS  Google Scholar 

  22. D.L. Bourell, H.L. Marcus, J.W. Barlow, and J.J. Beaman: Int. J. Powder Metall., 1992, vol. 28 (4), pp. 369–81.

    CAS  Google Scholar 

  23. D.E. Bunnell, S. Das, D.L. Bourell, J.B. Beaman, and H.L. Marcus: Proc. Solid Freeform Fabrication Symp., The University of Texas at Austin, Austin, TX, 1995, pp. 440–47.

    Google Scholar 

  24. G. Lewis and E. Schlienger: Mater. Design, 2000, vol. 21, pp. 417–23.

    Article  CAS  Google Scholar 

  25. Y.P. Kathuria: Surface Coatings Technol., 1999, vols. 116–119, pp. 643–47.

    Article  Google Scholar 

  26. A. Simchi, F. Petzoldt, and H. Pohl: Int. J. Powder Metall., 2001, vol. 37 (2), pp. 49–61.

    CAS  Google Scholar 

  27. A. Simchi, F. Petzoldt, H. Pohl, and H. Löffler: P/M Sci. Technol. Briefs, 2001, vol. 3 (1), pp. 5–9.

    CAS  Google Scholar 

  28. A. Simchi, H. Pohl, and F. Petzoldt: Proc. Rapid Conf., Fraunhofer Allianz Rapid Prototyping, Magdeburg, Germany, Amsterdam, May 28–30, 2001, pp. 292–98.

    Google Scholar 

  29. A. Simchi, F. Petzoldt, H. Pohl, and H. Löffler: Rapid Prototyping & Rapid Tooling Newsletter, Danish Technology Institute, Aarhus, Denmark, 2000, vol. 4, pp. 4–5.

    Google Scholar 

  30. F. Petzoldt, A. Simchi, H. Pohl, and H. Loffler: Paper presented at PM World Congr. & Exhib., Kyoto, Japan, 2000.

  31. A. Simchi, F. Petzoldt, and H. Pohl: J. Mater. Processing Technol., 2003, vol. 141 (3), pp. 319–28.

    Article  CAS  Google Scholar 

  32. A. Simchi and H. Pohl: Mater. Sci. Eng., 2003, vol. 359A (1–2), pp. 119–28.

    Google Scholar 

  33. Standard Test Methods for Metal Powder and Powder Metallurgy Products, Metal Powder Industries Federation, Princeton, NJ, 1986.

  34. W. O’Nill, C.J. Sutcliffe, R. Morgan, and K.K.B. Hon: Proc. Solid Freeform Fabrication Symp., The University of Texas at Austin, Austin, TX, 1998, pp. 147–59.

    Google Scholar 

  35. L. Pawlowski: J. Thermal Spray Technol., 1999, vol. 8, pp. 279–95.

    Article  CAS  Google Scholar 

  36. D.I. Pantelis and G. Pantazopoulos: in Lasers in Surface Engineering, N.B. Dahorte, ed., ASM INTERNATIONAL, Materials Park, OH, 1998, pp. 357–94.

    Google Scholar 

  37. S. Das: Proc. Solid Freeform Fabrication Symp., The University of Texas at Austin, Austin, TX, 2001, pp. 102–09.

    Google Scholar 

  38. N. Tolochko, S.E. Mozzharrov, N.V. Sobolenko, Yu. V. Khlopkov, I.A. Yadroitsev, and V.B. Mikhailov: J. Adv. Mater., 1995, vol. 2 (2), pp. 151–57.

    Google Scholar 

  39. Y. Kizaki, H. Azuma, S. Yamazaki, H. Sugimoto, and S. Takagi: Jpn. J. Appl. Phys., 1993, vol. 32 (1A), pp. 205–12.

    Article  CAS  Google Scholar 

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  1. the Department of Materials Science and Engineering, Sharif University of Technology, Tehran, Iran

    A. Simchi (Associate Professor)

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  1. A. Simchi
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Simchi, A. The role of particle size on the laser sintering of iron powder. Metall Mater Trans B 35, 937–948 (2004). https://doi.org/10.1007/s11663-004-0088-3

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