journal article·2026-09

Multiscale investigation of pore and crack formation during selective laser melting of pure tungsten: simulation and experimental validation

Meng Guo, Shilin Xia

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Abstract

Abstract Selective laser melting of pure tungsten has always been a challenge due to its intrinsic properties such as high melting point, high surface tension and dynamic viscosity. In order to reveal the physical phenomenon during SLM-processed pure tungsten, a transient mesoscale model was developed by finite volume method (FVM). The temperature evolution and thermodynamic behavior within the molten pool were investigated. The simulation results demonstrated that the peak temperature and cooling rate were enhanced as the laser power increased. The peaking temperature and cooling rate reached 5742 K and 4.66 \(\:\times\:\) 10 7 K/s using a high laser power of 350 W, respectively. Accordingly, the long liquid lifetime of 182 µs was obtained. At a high laser power of 350 W, the velocity vectors within the molten pool were intensified obviously, generating a strong mass transfer. A regular molten pool with a large width of 62 µm was obtained, which was favorable to metallurgical bonding with adjacent scanning tracks. The laser power played an important role in influencing the surface morphologies of SLM-processed tungsten parts. At a relatively low laser power of 200 W, the scanning track was discontinuous with a large number of unmelted particles. Simultaneously, the corresponding SLM-processed tungsten parts were observed with large pores. However, as a high laser power of 350 W was applied, the top surface of scanning track was continuous with regular liquid flow. Under this situation, the corresponding SLM-processed tungsten part was nearly free of pores. Moreover, the cracks were inevitable regardless of the applied laser powers and the formation mechanism of cracks was revealed. Based on the simulation results of SLM-processed tungsten, the available methods used to reduce the cracks were proposed.
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Research context

OpenAlex topics: Additive Manufacturing Materials and Processes · Laser Material Processing Techniques · High Entropy Alloys Studies

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References (38)

Show source-provided references
1. You H, Fu G, Jin S et al (2025) Advances in laser powder bed fusion of hard-to-weld superalloys: a comprehensive review. Mater Des 260:114932. https://doi.org/10.1016/j.matdes.2025.11493210.1016/j.matdes.2025.114932 ↗
2. Archaryagie KCS, Tang Y (2025) Enhancing powder bed quality in laser powder bed fusion: a review of monitoring, data processing, and adaptive control strategies. J Manuf Process 149:276–304. https://doi.org/10.1016/j.jmapro.2025.05.05810.1016/j.jmapro.2025.05.058 ↗
3. Hassan MZ, Aufa AN, Brytan Z et al (2025) Selective laser melting of magnesium alloys for biomedical applications: Microstructure to clinical translation. J Mater Res Technol 39:660–691. https://doi.org/10.1016/j.jmrt.2025.09.13710.1016/j.jmrt.2025.09.137 ↗
4. Seabra M, Azevedo J, Araújo A et al (2016) Selective laser melting (SLM) and topology optimization for lighter aerospace componentes. Procedia Struct Integr 1:289–296. https://doi.org/10.1016/j.prostr.2016.02.03910.1016/j.prostr.2016.02.039 ↗
5. Chandra S, Radhakrishnan J, Huang S et al (2025) Solidification in metal additive manufacturing: challenges, solutions, and opportunities. Prog Mater Sci 148:101361. https://doi.org/10.1016/j.pmatsci.2024.10136110.1016/j.pmatsci.2024.101361 ↗
6. Abd-Elaziem W, Elkatatny S, Abd-Elaziem AE et al (2022) On the current research progress of metallic materials fabricated by laser powder bed fusion process: a review. J Mater Res Technol 20:681–707. https://doi.org/10.1016/j.jmrt.2022.07.08510.1016/j.jmrt.2022.07.085 ↗
7. Kumar J, Ramalingam MS, Sharma S et al (2026) Additive manufacturing of refractory materials: Perspective, prospective, and challenges – Review. J Alloys Compd 1051:186018. https://doi.org/10.1016/j.jallcom.2026.18601810.1016/j.jallcom.2026.186018 ↗
8. Butler BG, Paramore JD, Ligda JP et al (2018) Mechanisms of deformation and ductility in tungsten – A review. Int J Refract Metals Hard Mater 75:248–261. https://doi.org/10.1016/j.ijrmhm.2018.04.02110.1016/j.ijrmhm.2018.04.021 ↗
9. Neu R, Riesch J, Coenen JW et al (2016) Advanced tungsten materials for plasma-facing components of DEMO and fusion power plants. Fusion Eng Des 109–111:1046–1052. https://doi.org/10.1016/j.fusengdes.2016.01.02710.1016/j.fusengdes.2016.01.027 ↗
10. Jiang M, Yang Y, Han C et al (2024) Defect formation mechanism and suppression strategy in additively manufactured tungsten grid thin-wall structures via laser powder bed fusion. J Manuf Process 120:222–233. https://doi.org/10.1016/j.jmapro.2024.04.04210.1016/j.jmapro.2024.04.042 ↗
11. Sharma S, Krishna KVM, Joshi SS et al (2023) Laser based additive manufacturing of tungsten: Multi-scale thermo-kinetic and thermo-mechanical computational model and experiments. Acta Mater 259:119244. https://doi.org/10.1016/j.actamat.2023.11924410.1016/j.actamat.2023.119244 ↗
12. Liang Z, Wu J, Liu C, Cui Y (2025) Microcracking in additively manufactured tungsten: experiment and a nano-micro-macro multiscale model. Int J Plast 186:104264. https://doi.org/10.1016/j.ijplas.2025.10426410.1016/j.ijplas.2025.104264 ↗
13. Wu YC, Hwang WS, San CH et al (2018) Parametric study of surface morphology for selective laser melting on Ti6Al4V powder bed with numerical and experimental methods. Int J Mater Form 11:807–813. https://doi.org/10.1007/s12289-017-1391-210.1007/s12289-017-1391-2 ↗
14. Qadeer A, Lone AS, Akhtar SS et al (2025) Prediction and control of structured porosity in laser powder bed fusion (LPBF) additive manufacturing using multi-scale modeling. Mater Des 258:114627. https://doi.org/10.1016/j.matdes.2025.11462710.1016/j.matdes.2025.114627 ↗
15. Yang Z, Wang W, Chen Y et al (2024) An experimental and numerical study on the evolution of pores and its effect on the tensile properties of LPBF Invar36 with different energy density. J Mater Res Technol 31:3064–3078. https://doi.org/10.1016/j.jmrt.2024.07.02610.1016/j.jmrt.2024.07.026 ↗
16. Liu D, Pan Y, Hou H, Zhao Y (2026) Pore evolution and porosity mitigation in laser powder bed fusion of Ni-Cr-Fe based superalloy. Int J Heat Mass Transf 255:127781. https://doi.org/10.1016/j.ijheatmasstransfer.2025.12778110.1016/j.ijheatmasstransfer.2025.127781 ↗
17. Guo M, Gu D, Xi L et al (2019) Formation of scanning tracks during Selective Laser Melting (SLM) of pure tungsten powder: Morphology, geometric features and forming mechanisms. Int J Refract Metals Hard Mater 79:37–46. https://doi.org/10.1016/j.ijrmhm.2018.11.00310.1016/j.ijrmhm.2018.11.003 ↗
18. Yuan P, Gu D (2015) Molten pool behaviour and its physical mechanism during selective laser melting of TiC/AlSi10Mg nanocomposites: simulation and experiments. J Phys D Appl Phys 48:35303. https://doi.org/10.1088/0022-3727/48/3/03530310.1088/0022-3727/48/3/035303 ↗
19. Xia M, Gu D, Yu G et al (2016) Selective laser melting 3D printing of Ni-based superalloy: understanding thermodynamic mechanisms. Sci Bull 61:1013–1022. https://doi.org/10.1007/s11434-016-1098-710.1007/s11434-016-1098-7 ↗
20. Xia M, Gu D, Yu G et al (2017) Porosity evolution and its thermodynamic mechanism of randomly packed powder-bed during selective laser melting of Inconel 718 alloy. Int J Mach Tools Manuf 116:96–106. https://doi.org/10.1016/j.ijmachtools.2017.01.00510.1016/j.ijmachtools.2017.01.005 ↗
21. Wang D, Yu C, Zhou X et al (2017) Dense pure tungsten fabricated by selective laser melting. Appl Sci 7:430. https://doi.org/10.3390/app704043010.3390/app7040430 ↗
22. Paradis PF, Ishikawa T, Fujii R, Yoda S (2006) Thermophysical properties of molten tungsten measured with an electrostatic levitator. Heat Transf-Asian Re 35:152–164. https://doi.org/10.1002/htj.2010110.1002/htj.20101 ↗
23. Tolias P (2017) Analytical expressions for thermophysical properties of solid and liquid tungsten relevant for fusion applications. Nucl Mater Energy 13:42–57. https://doi.org/10.1016/j.nme.2017.08.00210.1016/j.nme.2017.08.002 ↗
24. Das M, Balla VK, Basu D et al (2010) Laser processing of SiC-particle-reinforced coating on titanium. Scr Mater 63:438–441. https://doi.org/10.1016/j.scriptamat.2010.04.04410.1016/j.scriptamat.2010.04.044 ↗
25. Paradis PF, Ishikawa T, Yoda S (2005) Viscosity of liquid undercooled tungsten. J Appl Phys 97:106101. https://doi.org/10.1063/1.189643210.1063/1.1896432 ↗
26. Romano J, Ladani L, Razmi J, Sadowski M (2015) Temperature distribution and melt geometry in laser and electron-beam melting processes - a comparison among common materials. Addit Manuf 8:1–11. https://doi.org/10.1016/j.addma.2015.07.00310.1016/j.addma.2015.07.003 ↗
27. Le KQ, Tang C, Wong CH (2019) On the study of keyhole-mode melting in selective laser melting process. Int J Therm Sci 145:105992. https://doi.org/10.1016/j.ijthermalsci.2019.10599210.1016/j.ijthermalsci.2019.105992 ↗
28. Yu G, Gu D, Dai D et al (2016) Influence of processing parameters on laser penetration depth and melting/re-melting densification during selective laser melting of aluminum alloy. Appl Phys A Mater Sci Process 122:1–12. https://doi.org/10.1007/s00339-016-0428-610.1007/s00339-016-0428-6 ↗
29. Wang DZ, Li KL, Yu CF et al (2019) Cracking behavior in additively manufactured pure tungsten. Acta Metall Sin 32:127–135. https://doi.org/10.1007/s40195-018-0752-210.1007/s40195-018-0752-2 ↗
30. Wang D, Wang Z, Li K et al (2019) Cracking in laser additively manufactured W: Initiation mechanism and a suppression approach by alloying. Mater Des 162:384–393. https://doi.org/10.1016/j.matdes.2018.12.01010.1016/j.matdes.2018.12.010 ↗
31. Németh AAN, Reiser J, Armstrong DEJ, Rieth M (2015) The nature of the brittle-to-ductile transition of ultra fine grained tungsten (W) foil. Int J Refract Met Hard Mater 50:9–15. https://doi.org/10.1016/j.ijrmhm.2014.11.00510.1016/j.ijrmhm.2014.11.005 ↗
32. Arakcheev AS, Huber A, Wirtz M et al (2015) Theoretical investigation of crack formation in tungsten after heat loads. J Nucl Mater 463:246–249. https://doi.org/10.1016/j.jnucmat.2014.10.09010.1016/j.jnucmat.2014.10.090 ↗
33. Li C, Zhu D, Li X et al (2017) Thermal–stress analysis on the crack formation of tungsten during fusion relevant transient heat loads. Nucl Mater Energy 13:68–73. https://doi.org/10.1016/j.nme.2017.06.00810.1016/j.nme.2017.06.008 ↗
34. Budaev VP, Martynenko YV, Karpov AV et al (2015) Tungsten recrystallization and cracking under ITER-relevant heat loads. J Nucl Mater 463:237–240. https://doi.org/10.1016/j.jnucmat.2014.11.12910.1016/j.jnucmat.2014.11.129 ↗
35. Zheng B, Zhou Y, Smugeresky JE et al (2008) Thermal behavior and microstructural evolution during laser deposition with laser-engineered net shaping: Part I. Numerical calculations. Metall Mater Trans A Phys Metall Mater Sci 39:2228–2236. https://doi.org/10.1007/s11661-008-9557-710.1007/s11661-008-9557-7 ↗
36. Xia Z, Wang H, Xu Q (2012) The stress relief mechanism in laser irradiating on porous films. Opt Commun 285:70–76. https://doi.org/10.1016/j.optcom.2011.09.01210.1016/j.optcom.2011.09.012 ↗
37. Ji L, Wei S, Wang Z et al (2024) Current status and potential strategies for crack-free tungsten by laser powder bed fusion: A review. J Manuf Process 131:2535–2554. https://doi.org/10.1016/j.jmapro.2024.10.02010.1016/j.jmapro.2024.10.020 ↗
38. Sowards JW, Crabtree E, O’Connor A et al (2026) Solidification cracking of refractory alloys: a computational and machine learning study to investigate composition-dependence for improved weldability and additive manufacturability. Mater Des 263:115679. https://doi.org/10.1016/j.matdes.2026.11567910.1016/j.matdes.2026.115679 ↗