Research Paper:
Study on Laser Scan Strategy for Correcting Anisotropic Residual Stress Distribution and Reducing Warpage in Structures Fabricated by PBF-LB/M
Atsushi Ezura*, , Satoshi Abe**, Tatsuaki Furumoto** , Toshihiko Sasaki** , and Jiro Sakamoto**
*Sanjo City University
5002-5 Kamisugoro, Sanjo-shi, Niigata 955-0091, Japan
Corresponding author
**Kanazawa University
Kanazawa, Japan
Metal-based powder bed fusion with a laser beam (PBF-LB/M) can be applied to fabricate high-accuracy structures compared with other metal additive manufacturing (AM) methods. The rapid solidification of metal powder formed by laser irradiation introduces heterogeneous residual stress, which causes deformation and cracking of the structure. This, in turn, results in the deterioration of quality. In this study, the influence of the laser scan strategy on the residual stress distribution and warpage of the structure was investigated. Using maraging steel powder with an average particle size of 32.5 μm, the structures were constructed using several laser scan strategies at a wavelength of 1070 nm. The residual stress distributions on the surface of the structures were measured by the cosα method by applying X-ray diffraction (XRD). In addition, the warpage of the reverse side of the substrate as a foundation of the structure was measured by a stylus-type surface roughness measuring instrument. The results clarified that the structures constructed by unidirectional scan directions had a tensile residual stress that was generated parallel to the laser scan direction. Meanwhile, the compressive residual stress was generated perpendicular to the laser scan direction. The large warpage was aligned with the laser scan direction and tensile residual stress. When the laser scan direction was rotated by 90° for each layer, the residual stress distribution was generated with a cruciform shape. It was indicated that this residual distribution was caused by a laser scan on the top surface and a lower layer. The anisotropic residual stress distribution and reduction of warpage could be corrected by rotating the laser scan direction by 15° in each layer.
- [1] A. Speidel, R. Sélo, I. Bisterov, J. M. Smith, and A. T. Clare, “Post processing of additively manufactured parts using electrochemical jet machining,” Mater. Lett., Vol.292, 129671, 2021. https://doi.org/10.1016/j.matlet.2021.129671
- [2] W. E. Frazier, “Metal additive manufacturing: A review,” J. Mater. Eng. Perform., Vol.23, No.6, pp. 1917-1928, 2014. https://doi.org/10.1007/s11665-014-0958-z
- [3] M. Yamaguchi, T. Furumoto, Y. Tanabe, S. Yamada, M. Osaki, Y. Hashimoto, T. Koyano, and A. Hosokawa, “Effects of the powder morphology, size distribution, and characteristics on the singletrack formation in selective laser melting of H13 steel,” J. Adv. Mech. Des., Sys. Manuf., Vol.15, No.3, JAMDSM0035, 2021. https://doi.org/10.1299/jamdsm.2021jamdsm0035
- [4] K. Egashira, T. Furumoto, K. Hishida, S. Abe, T. Koyano, Y. Hashimoto, and A. Hosokawa, “Formation mechanism of pores inside structure fabricated by metal-based additive manufacturing,” Int. J. Automation Technol., Vol.13, No.3, pp. 330-337, 2019. https://doi.org/10.20965/ijat.2019.p0330
- [5] J. L. Z. Li, M. R. Alkahari, N. A. B. Rosli, R. Hasan, M. N. Sudin, and F. R. Ramli, “Review of wire arc additive manufacturing for 3D metal printing,” Int. J. Automation Technol., Vol.13, No.3, pp. 346-353, 2019. https://doi.org/10.20965/ijat.2019.p0346
- [6] N. Ikeo, H. Fukuda, A. Matsugaki, T. Inoue, A. Serizawa, T. Matsuzaka, T. Ishimoto, R. Ozasa, O. Gokcekaya, and T. Nakano, “3D puzzle in cube pattern for anisotropic/isotropic mechanical control of structure fabricated by metal additive manufacturing,” Crystals, Vol.11, No.8, 959, 2021. https://doi.org/10.3390/cryst11080959
- [7] T. Saraçyakupoğlu, “Usage of additive manufacturing and topology optimization process for weight reduction studies in the aviation industry,” Adv. Sci. Technol. Eng. Syst. J., Vol.6, No.2, pp. 815-820, 2021. https://doi.org/10.25046/aj060294
- [8] H. Tiismus, A. Kallaste, T. Vaimann, and A. Rassõlkin, “State of the art of additively manufactured electromagnetic materials for topology optimized electrical machines,” Addit. Manuf., Vol.55, 102778, 2022. https://doi.org/10.1016/j.addma.2022.102778
- [9] M. Kumaran and V. Senthilkumar, “Generative design and topology optimization of analysis and repair work of industrial robot arm manufactured using additive manufacturing technology,” IOP Conf. Series: Mater. Sci. and Eng., Vol.1012, No.1, 012036, 2021. https://doi.org/10.1088/1757-899X/1012/1/012036
- [10] A. Fedorenko, B. Fedulov, Y. Kuzminova, S. Evlashin, O. Staroverov, M. Tretyakov, E. Lomakin, and I. Akhatov, “Anisotropy of Mechanical Properties and Residual Stress in Additively Manufactured 316L Specimens,” Mater., Vol.14, No.23, 7176, 2021. https://doi.org/10.3390/ma14237176
- [11] T. Ishimoto, K. Hagihara, K. Hisamoto, S. H. Sun, and T. Nakano, “Crystallographic texture control of beta-type Ti–15Mo–5Zr–3Al alloy by selective laser melting for the development of novel implants with a biocompatible low Young’s modulus,” Scr. Mater., Vol.132, pp. 34-38, 2017. https://doi.org/10.1016/j.scriptamat.2016.12.038
- [12] H. Torbati-Sarraf, I. Ghamarian, B. Poorganji, and S. A. Torbati-Sarraf, “An Investigation on the role of crystallographic texture on anisotropic electrochemical behavior of a commercially pure nickel manufactured by laser powder bed fusion (L-PBF) additive manufacturing,” Electrochem. Acta, Vol.354, 136694, 2020. https://doi.org/10.1016/j.electacta.2020.136694
- [13] T. Kimura and T. Nakamoto, “Microstructures and mechanical properties of A356 (AlSi7Mg0.3) aluminum alloy fabricated by selective laser melting,” Mater. & Des., Vol.89, pp. 1294-1301, 2016. https://doi.org/10.1016/j.matdes.2015.10.065
- [14] B. Meier, N. Godja, F. Warchomicka, C. Belei, S. Schäfer, A. Schindel, G. Palcynski, R. Kaindl, W. Waldhauser, and C. Sommitsch, “Influences of Surface, Heat Treatment, and Print Orientation on the Anisotropy of the Mechanical Properties and the Impact Strength of Ti 6Al 4V Processed by Laser Powder Bed Fusion,” J. Manuf. and Mater. Process., Vol.6, No.4, 87, 2022. https://doi.org/10.3390/jmmp6040087
- [15] J. Schröder, A. Evans, E. Polatidis, J. Čapek, G. Mohr, I. Serrano-Munoz, and G. Bruno, “Understanding the impact of texture on the micromechanical anisotropy of laser powder bed fused Inconel 718,” J. Mater. Sci., Vol.57, No.31, pp. 15036-15058, 2022. https://doi.org/10.1007/s10853-022-07499-9
- [16] X. Zhang, H. Xu, Z. Li, A. Dong, D. Du, L. Lei, G. Zhang, D. Wang, G. Zhu, and B. Sun, “Effect of the scan strategy on microstructure and mechanical anisotropy of Hastelloy X superalloy produced by Laser Powder Bed Fusion,” Mater. Charact., Vol.173, 110951, 2021. https://doi.org/10.1016/j.matchar.2021.110951
- [17] E. W. Hovig, A. S. Azar, F. Grytten, K. Sørby, and E. Andreassen, “Determination of anisotropic mechanical properties for materials processed by laser powder bed fusion,” Add. in Mater. Sci. and Eng., Vol.2018, 7650303, 2018. https://doi.org/10.1155/2018/7650303
- [18] T. Furumoto, R. Ogura, K. Hishida, A. Hosokawa, T. Koyano, S. Abe, and T. Ueda, “Study on deformation restraining of metal structure fabricated by selective laser melting,” J. Mater. Process. Technol., Vol.245, pp. 207-214, 2017. https://doi.org/10.1016/j.jmatprotec.2017.02.017
- [19] A. Takezawa, H. Guo, R. Kobayashi, Q. Chen, and A. C. To, “Simultaneous optimization of hatching orientations and lattice density distribution for residual warpage reduction in laser powder bed fusion considering layerwise residual stress stacking,” Addit. Manuf., Vol.60, 103194, 2022. https://doi.org/10.1016/j.addma.2022.103194
- [20] P. Promoppatum and V. Uthaisangsuk, “Part scale estimation of residual stress development in laser powder bed fusion additive manufacturing of Inconel 718,” Finite Elem. Anal. Des., Vol.189, 103528, 2021. https://doi.org/10.1016/j.finel.2021.103528
- [21] J. Robinson, I. Ashton, P. Fox, E. Jones, and C. Sutcliffe, “Determination of the effect of scan strategy on residual stress in laser powder bed fusion additive manufacturing,” Addit. Manuf., Vol.23, pp. 13-24, 2018. https://doi.org/10.1016/j.addma.2018.07.001
- [22] N. C. Levkulich, S. L. Semiatin, J. E. Gockel, J. R. Middendorf, A. T. DeWald, and N. W. Klingbeil, “The effect of process parameters on residual stress evolution and distortion in the laser powder bed fusion of Ti-6Al-4V,” Addit. Manuf., Vol.28, pp. 475-484, 2019. https://doi.org/10.1016/j.addma.2019.05.015
- [23] H. Ali, H. Ghadbeigi, and K. Mumtaz, “Effect of scan strategies on residual stress and mechanical properties of Selective Laser Melted Ti6Al4V,” Mater. Sci. and Eng. A, Vol.712, pp. 175-187, 2018. https://doi.org/10.1016/j.msea.2017.11.103
- [24] J. Song, W. Wu, L. Zhang, B. He, L. Lu, X. Ni, Q. Long, and G. Zhu, “Role of scan strategy on residual stress distribution in Ti-6Al-4V alloy prepared by selective laser melting,” Opt., Vol.170, pp. 342-352, 2018. https://doi.org/10.1016/j.ijleo.2018.05.128
- [25] M. Masoomi, S. M. Thompson, and N. Shamsaei, “Laser powder bed fusion of Ti-6Al-4V parts: Thermal modeling and mechanical implications,” Int. J. Mach. Tools and Manuf., Vol.118, pp. 73-90, 2017. https://doi.org/10.1016/j.ijmachtools.2017.04.007
- [26] M. F. Zaeh and G. Branner, “Investigations on residual stresses and deformations in selective laser melting,” Prod. Eng., Vol.4, No.1, pp. 35-45, 2010. https://doi.org/10.1007/s11740-009-0192-y
- [27] K. Artzt, T. Mishurova, P. P. Bauer, J. Gussone, P. Barriobero-Vila, S. Evsevleev, G. Bruno, G. Requena, and J. Haubrich, “Pandora’s box–influence of contour parameters on roughness and subsurface residual stresses in laser powder bed fusion of Ti-6Al-4V,” Mater., Vol.13, No.15, 3348, 2020. https://doi.org/10.3390/ma13153348
- [28] S. Taira, K. Tanaka, and T. Yamazaki, “A method of X-ray microbeam measurement of local stress and its application to fatigue crack growth problems,” J. Soc. Mater. Sci. Japan, Vol.27, No.294, pp. 251-256, 1978 (in Japanese). https://doi.org/10.2472/jsms.27.251
- [29] T. Miyazaki and T. Sasaki, “X-ray stress measurement with two-dimensional detector based on Fourier analysis,” Int. J. Mater. Res., Vol.105, No.9, pp. 922-927, 2014. https://doi.org/10.3139/146.111101
- [30] E. Mirkoohi, H. C. Tran, Y. L. Lo, Y. C. Chang, H. Y. Lin, and S. Y. Liang, “Mechanics modeling of residual stress considering effect of preheating in laser powder bed fusion,” J. Manuf. Mater. Process., Vol.46, No.5, 5020046, 2021. https://doi.org/10.3390/jmmp5020046
- [31] J. Robinson, I. Ashton, P. Fox, E. Jones, and C. Sutcliffe, “Determination of the effect of scan strategy on residual stress in laser powder bed fusion additive manufacturing,” Addit. Manuf., Vol.23, pp. 13-24, 2018. https://doi.org/10.1016/j.addma.2018.07.001
- [32] M. Balbaa, S. Mekhiel, M. Elbestawi, and J. McIsaac, “On selective laser melting of Inconel 718: Densification, surface roughness, and residual stresses,” Mater. & Des., Vol.193, 108818, 2020. https://doi.org/10.1016/j.matdes.2020.108818
This article is published under a Creative Commons Attribution-NoDerivatives 4.0 Internationa License.