LAZER TOZ YATAK FÜZYONU İLE ÜRETİLEN TI-6AL-4V ALAŞIMININ YÜZEY TOPOGRAFYASININ KARAKTERİZASYONU

Öz

Lazer toz yatağı füzyonu (L-PBF), yüksek enerjili bir lazerin üç boyutlu bileşenler üretmek için metalik toz katmanlarını seçici olarak ergittiği bir eklemeli üretim süreci sınıfıdır. L-PBF karmaşık geometrilerin üretiminde önemli ilerlemeler sağlarken, üretilen parçaların düşük yüzey kalitesi hala sürecin bir dezavantajıdır. Üretilen parçalardaki yüksek yüzey pürüzlülüğü temel olarak eritme, katılaştırma ve soğutma süreçleri sırasındaki karmaşık termal geçmişten kaynaklanmaktadır. Bu çalışmada, Ti-6Al-4V tozundan L-PBF prosesi ile dikdörtgen numuneler üretilmiştir. Numunelerin hem üst hem de yan yüzeylerinin yüzey topografisi, yüzey pürüzlülüğü test cihazı ve taramalı elektron mikroskobu (SEM) kullanılarak karakterize edilmiştir. Yüzey pürüzlülüğünün kaynaklarının iki yönelim arasında önemli ölçüde farklılık gösterdiği bulunmuştur. Yan yüzeylerde, pürüzlülük ağırlıklı olarak kısmen erimiş toz partiküllerinin yapışmasından kaynaklanmaktadır. Aksine, üst yüzey pürüzlülüğü çeşitli kusurlardan etkilenir ve yumrulama fenomeni oldukça pürüzlü yüzeyler oluşturmada önemli bir rol oynar.

Anahtar Kelimeler

• Eklemeli İmalat
• Lazer Toz Yatak Füzyon
• Ti-6Al-4V
• Yüzey Pürüzlülüğü

CHARACTERIZATION OF THE SURFACE TOPOGRAPHY OF THE TI-6AL-4V ALLOY FABRICATED BY LASER POWDER BED FUSION

Öz

Laser powder bed fusion (L-PBF) is a class of additive manufacturing processes in which a high-energy laser selectively melts layers of metallic powder to fabricate three-dimensional components. While L-PBF enables significant advancements in the manufacturing of complex geometries, poor surface quality of the as-built parts is still a drawback of the process. High surface roughness in as-built parts is primarily caused by the complex thermal history during the melting, solidification, and cooling processes. In this study, rectangular samples were fabricated from Ti-6Al-4V powder by the L-PBF process. Surface topography of the samples in as-build state, both top and side surfaces, was characterized using a surface roughness tester and a scanning electron microscope (SEM). The origins of surface roughness were found to differ significantly between the two orientations. On the side surfaces, roughness is predominantly due to the attachment of partially melted powder particles. In contrast, the top surface roughness is influenced by several defects, with balling phenomena playing a major role in generating highly rough surfaces.

Anahtar Kelimeler

• Additive Manufacturing
• Laser Powder Bed Fusion
• Ti-6Al-4V
• Surface Roughness

Etik Beyan

This work was supported by the Alexander von Humboldt Foundation (www.humboldt-foundation.de).

Teşekkür

The author would like to thank the team in Access e.V. (https://access-technology.de/) to assist the author to perform 3D-printing and sample characterizations.

Kaynakça

1. Ahn, D.-G., 2021. Directed Energy Deposition (DED) Process: State of the Art. International Journal of Precision Engineering and Manufacturing-Green Technology, 8, 703-742.
2. Bartels, D., Nikas, D., März, R., Marschall, M., Schrauder, J., Merklein, M., Şelte, A., & Krakhmalev, P., 2025. Directed energy deposition of chromium-molybdenum-vanadium cold work tool steel Vanadis 4 Extra©. Journal of Materials Research and Technology, 38, 1573-1580.
3. Boban, J., Ahmed, A., Jithinraj, E. K., Rahman, M. A., & Rahman, M., 2022. Polishing of additive manufactured metallic components: retrospect on existing methods and future prospects. The International Journal of Advanced Manufacturing Technology, 121, 83-125.
4. Calignano, F., Manfredi, D., Ambrosio, E. P., Iuliano, L., & Fino, P., 2013. Influence of process parameters on surface roughness of aluminum parts produced by DMLS. The International Journal of Advanced Manufacturing Technology, 67, 2743-2751.
5. Çam, G., 2022. Prospects of producing aluminum parts by wire arc additive manufacturing (WAAM). Materials Today: Proceedings, 62, 77-85.
6. Çam, G., & Günen, A., 2024. Challenges and opportunities in the production of magnesium parts by directed energy deposition processes. Journal of Magnesium and Alloys, 12, 1663-1686.
7. Çam, G., İpekoğlu, G., Bohm, K. H., & Koçak, M., 2006. Investigation into the microstructure and mechanical properties of diffusion bonded TiAl alloys. Journal of Materials Science, 41, 5273-5282.
8. Cao, S., Zou, Y., Lim, C. V. S., & Wu, X., 2021. Review of laser powder bed fusion (LPBF) fabricated Ti-6Al-4V: process, post-process treatment, microstructure, and property. Light: Advanced Manufacturing, 2, 313-332.

9. Chen, Z., Wu, X., Tomus, D., & Davies, C. H. J., 2018. Surface roughness of Selective Laser Melted Ti-6Al-4V alloy components. Additive Manufacturing, 21, 91-103.
10. DebRoy, T., Wei, H. L., Zuback, J. S., Mukherjee, T., Elmer, J. W., Milewski, J. O., Beese, A. M., Wilson-Heid, A., De, A., & Zhang, W., 2018. Additive manufacturing of metallic components – Process, structure and properties. Progress in Materials Science, 92, 112-224.
11. Gu, D., & Shen, Y., 2009. Balling phenomena in direct laser sintering of stainless steel powder: Metallurgical mechanisms and control methods. Materials & Design, 30, 2903-2910.
12. Gussone, J., Bugelnig, K., Barriobero-Vila, P., da Silva, J. C., Hecht, U., Dresbach, C., Sket, F., Cloetens, P., Stark, A., Schell, N., Haubrich, J., & Requena, G., 2020. Ultrafine eutectic Ti-Fe-based alloys processed by additive manufacturing – A new candidate for high temperature applications. Applied Materials Today, 20, 100767.
13. Hecht, U., Vayyala, A., Barriobero-Vila, P., Navaeilavasani, N., Gein, S., Cazic, I., & Mayer, J., 2023. Microstructure evolution in the hypo-eutectic alloy Al0.75CrFeNi2.1 manufactured by laser powder bed fusion and subsequent annealing. Materials Science and Engineering: A, 862, 144315.
14. King, W. E., Anderson, A. T., Ferencz, R. M., Hodge, N. E., Kamath, C., Khairallah, S. A., & Rubenchik, A. M., 2015. Laser powder bed fusion additive manufacturing of metals; physics, computational, and materials challenges. Applied Physics Reviews, 2,
15. Kocaman, E., Gürol, U., Günen, A., & Çam, G., 2025. Effect of post-deposition heat treatments on high-temperature wear and corrosion behavior of Inconel 625. Materials Today Communications, 42, 111101.
16. Liu, J., Zhao, K., Wang, X., & Li, H., 2024. Effect of Initial Surface Morphology and Laser Parameters on the Laser Polishing of Stainless Steel Manufactured by Laser Powder Bed Fusion. Materials, 17, 4968.
17. Osman RB, & MV., S., 2015. A critical review of dental implant materials with an emphasis on titanium versus zirconia. Materials 8(3), 932-958.
18. Poyraz, Ö., Solakoğlu, E. U., Ören, S., Tüzemen, C., & Akbulut, G., 2019. Toz yatağı katmanlı imalat prosesinde yüzey dokusu ve form karakterizasyonu. Gazi Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi, 34, 1653-1664.
19. Qiu, C., Panwisawas, C., Ward, M., Basoalto, H. C., Brooks, J. W., & Attallah, M. M., 2015. On the role of melt flow into the surface structure and porosity development during selective laser melting. Acta Materialia, 96, 72-79.
20. Rodríguez-Sánchez, M., Boccardo, A. D., Sadanand, S., Ghavimi, A., Busch, R., Sharangi, P., Ferrara, E., Barrera, G., Tiberto, P., Tourret, D., Gallino, I., & Pérez-Prado, M. T., 2025. Laser powder bed fusion of an Fe-based metallic glass using time delays. Additive Manufacturing, 110, 104922.
21. Seow, C. E., Coules, H. E., Wu, G., Khan, R. H. U., Xu, X., & Williams, S., 2019. Wire + Arc Additively Manufactured Inconel 718: Effect of post-deposition heat treatments on microstructure and tensile properties. Materials & Design, 183, 108157.
22. Silva, R. C. S., Agrelli, A., Andrade, A. N., Mendes-Marques, C. L., Arruda, I. R. S., Santos, L. R. L., Vasconcelos, N. F., & Machado, G., 2022. Titanium dental implants: an overview of applied nanobiotechnology to improve biocompatibility and prevent infections. Materials, 15, 3150.
23. Sizova, I., Sviridov, A., Bambach, M., Eisentraut, M., Hemes, S., Hecht, U., Marquardt, A., & Leyens, C., 2021. A study on hot-working as alternative post-processing method for titanium aluminides built by laser powder bed fusion and electron beam melting. Journal of Materials Processing Technology, 291, 117024.
24. Snyder, J. C., & Thole, K. A., 2020. Understanding Laser Powder Bed Fusion Surface Roughness. Journal of Manufacturing Science and Engineering, 142,
25. Spears, T. G., & Gold, S. A., 2016. In-process sensing in selective laser melting (SLM) additive manufacturing. Integrating Materials and Manufacturing Innovation, 5, 16-40.
26. Tolochko, N. K., Mozzharov, S. E., Yadroitsev, I. A., Laoui, T., Froyen, L., Titov, V. I., & Ignatiev, M. B., 2004. Balling processes during selective laser treatment of powders. Rapid Prototyping Journal, 10, 78-87.
27. Valentinčič, J., Koroth, J. E., & Zeidler, H., 2024. Advancements in surface finish for additive manufacturing of metal parts: a comprehensive review of plasma electrolytic polishing (PEP). Virtual and Physical Prototyping, 19, e2364222.
28. Zeidler, H., & Böttger-Hiller, F., 2022. Plasma-electrolytic polishing as a post-processing technology for additively manufactured parts. Chemie Ingenieur Technik, 94, 1024-1029.
29. Zhang, T., & Yuan, L., 2022. Understanding surface roughness on vertical surfaces of 316 L stainless steel in laser powder bed fusion additive manufacturing. Powder Technology, 411, 117957.