Toz yatağı katmanlı imalat prosesinde yüzey dokusu ve form karakterizasyonu

Öz

Toz yatağında lazer katmanlı (eklemeli) imalat sonrası elde edilen yüzey kalitesi, parçaların, boyutsal doğruluğu ve herhangi bir yüzey işlemi olmaksızın kullanımını sınırlandıran etkenlerden biridir. Bu durumun temel sebebi prosesin doğası gereği ortaya çıkan ve diğer katmanlı imalat proseslerinde de görülen merdiven etkisidir. Merdiven etkisi görülen bir komponent yüzeyindeki geometrik ve form hataları montaj edilebilirlik, akış performans düşüşü ve yorulma başta olmak üzere çok sayıda riski beraberinde getirmektedir. Merdiven etkisinin engellenmesi için katmanlı imalat proses parametreleri optimizasyonu, ikincil işlemler ile yüzey temizleme ve/veya proses modelleme uygulanabilir. Bunlar arasından ikincil işlemler, ek zaman ve maliyet ortaya çıkardığı için daha az tercih edilmektedir. Proses modellemede ise, literatürde kullanılan geometrik modellerin sadece katman kalınlığını dikkate alması, farklı malzeme ve proses parametreleri için yakınsama oranlarını yetersiz kılmaktadır. Bunlara ek olarak parametre optimizasyonu tek bir parçaya yönelik olduğunda, farklı geometrik unsurların etkileri görülememektedir. Bu çalışmada sırası ile düz, açılı ve farklı yuvarlatma yarıçaplarına sahip yenilikçi numune geometrileri tasarlanmış ve Inconel 625 malzemeden toz yatağında lazer katmanlı imalat ile üretilmiştir. Üretilen numuneler üzerinde yüzey dokusu ve form karakterizasyon incelemeleri gerçekleştirilmiştir. Farklı unsur ve ölçüler için elde edilen sonuçlar sunularak, geometrik özelliklere bağlı yüzey kalitesi ve form değişim eğilimleri elde edilmiş, parametrelerin etkileri tartışılmıştır.

Anahtar Kelimeler

• Toz yatağı katmanlı imalat,eklemeli imalat,yüzey dokusu karakterizasyonu

Öz

The surface quality obtained after laser powder bed additive manufacturing is one of the factors that limits the use of part without any surface treatment. The main reason of this situation is the stair effect form as a result of the layered nature of the process. Geometric and form errors on a component surface with a stair effect bring numerous risks, especially in terms of assembly operations, flow performance and fatigue resistance decrease. To prevent the stair effect and surface irregularities, parameter optimization, post processes and/or process modeling can be studied. Among these, post processes are less preferred because they result in additional time and cost. In the process modeling, the geometric models used in the literature only take into account the thickness of the layer, making the convergence rates for different material and process parameters inadequate. In addition, when the parameter optimization is directed for a single part, the effects of different geometrical elements cannot be seen. In this study, innovative test artifacts with flat, angled and curved faces were designed and produced with laser powder bed additive manufacturing of Inconel 625 material. Surface texture and form characterization studies were performed on the artifacts. By presenting the results obtained for different features and dimensions, surface texture and form change trends due to geometric properties were obtained and the effects of the parameters were discussed

Anahtar Kelimeler

• Powder bed fusion,additive manufacturing,surface texture characterization

Kaynakça

1. 1. ASTM F2792-12a, Standard Terminology for Additive Manufacturing Technologies, ASTM International, 2015.
2. 2. VDI 3404, Additive Manufacturing: Basics, Definitions, Processes, VDI, 2014.
3. 3. Levy G. N., Schindel R., Kruth J. P., Rapid manufacturing and rapid tooling with layer manufacturing (LM) technologies, state of the art and future perspectives, CIRP Annals-Manufacturing Technology, 52(2), 589-609, 2003.
4. 4. Poyraz Ö., Kuşhan M.C., Investigation of the effect of different process parameters for laser additive manufacturing of metals, Journal of the Faculty of Engineering and Architecture of Gazi University, 33 (2), 730-742, 2018.
5. 5. Hague R., Unlocking the design potential of rapid manufacturing, Rapid manufacturing: an industrial revolution for the digital age, John Wiley & Sons, Ltd., ABD, 2006
6. 6. Yasa E., Poyraz O., Solakoglu E.U., Akbulut G., Oren S., A Study on the Stair Stepping Effect in Direct Metal Laser Sintering of a Nickel-based Superalloy, Procedia CIRP, 45, 175-178, 2016.
7. 7. Herderick E., Additive manufacturing of metals: A review, Materials Science & Technology Conference, Ohio, ABD, 1413-1425, 16-20 October, 2011.
8. 8. Hague R., Campbell I., Dickens P., Implications on design of rapid manufacturing, Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 217 (1), 25-30, 2003.

9. 9. Yasa E., Demir F., Akbulut G., Cızıoğlu N., Pilatin S., Benchmarking Of Different Powder-Bed Metal Fusion Processes For Machine Selection in Additive Manufacturing, Proceedings of Solid Freeform Fabrication Symposium, Austin, Texas, ABD, 390-403, August, 2014.
10. 10. Poyraz Ö., Yasa E., Akbulut G., Orhangül A., Pilatin, S., Investigation of Support Structures for Direct Metal Laser Sintering (DMLS) of In625 Parts, Proceedings of the Solid Freeform Fabrication Symposium, Austin, Texas, ABD, 560-574, 7-9 August, 2015.
11. 11. Townsend A., Senin N., Blunt L., Leach R.K., Taylor J.S., Surface texture metrology for metal additive manufacturing: a review, Precision Engineering, 46 (2016) 34–47.
12. 12. Zecchino M., How to choose the correct stylus for any application. Veeco; 2005.
13. 13. Ross I., Kumstel J., Bremen S., Willenborg E., Laser polishing of laser additive manufactured surfaces made from Inconel 718 and ASTM F75. Achieving precision tolerances in additive manufacturing. In: ASPE 2015 Spring Topical Meeting, ASPE, 2015.
14. 14. Beard M., Ghita O., Evans K.E. Using Raman spectroscopy to monitor surface finish and roughness of components manufactured by selective laser sintering. J Raman Spectrosc 2011; 42:744–8.
15. 15. Krolczyk G., Raos P., Legutko S., Experimental analysis of surface roughnessand surface texture of machined and fused deposition modelled parts.Tehniˇcki Vjesnik—Tech Gaz 2014;21:217–21, 2014.
16. 16. Gomez C., Su R., Thompson A., DiSciacca J., Lawes S., Leach R.K., Optimization of surface measurement for metal additive manufacturing using coherence scanning interferometry, Optical Engineering, 56(11), 111714, 2017.
17. 17. Król M., Kujawa M., Dobrzański L.A., Tański T., Influence of technological parameters on additive manufacturing steel parts in Selective Laser Sintering, Archives of Materials Science and Engineering, Vol. 67, No. 2, pp 84-92, 2014.
18. 18. Taufik M., Jain P.K., Role of build orientation in layered manufacturing: a review, International Journal of Manufacturing Technology and Management, Vol. 27, No. 1-3, pp 47-73, 2013.
19. 19. Strano G., Hao L., Everson R. M., Evans K. E., Surface roughness analysis, modelling and prediction in selective laser melting. Journal of Materials Processing Technology, 213(4), 589-597, 2013.
20. 20. Gibson I., Rosen D.W., Stucker B., Post-Processing in Additive Manufacturing Technologies, Springer, New York, US, pp 415-435, 2010.
21. 21. Fischer M., Schöppner V., Finishing of ABS-M30 parts manufactured with fused deposition modeling with focus on dimensional accuracy, Proceedings of 25th Solid Freeform Fabrication Symposium, 923-934, 2014.
22. 22. Williams R.E., Walczyk D.F., Dang H.T., Using abrasive flow machining to seal and finish conformal channels in laminated tooling, Rapid Prototyping Journal 13/2 (2007) 64–75.
23. 23. Kumbhar N.N., Mulay A.V., Post Processing Methods used to Improve Surface Finish of Products which are Manufactured by Additive Manufacturing Technologies: A Review, J. Inst. Eng. India Ser. C (August 2018) 99(4):481–487.
24. 24. Uhlmann E., Schmiedel C., Wendler J., CFD Simulation for the abrasive machining process, Procedia CIRP 31 (2015) 209-214.
25. 25. Hague R., Mansour S., Saleh N., Material and design considerations for rapid manufacturing, International Journal of Production Research, Vol. 42, No. 22, pp 4691-4708, 2004.
26. 26. Thomas D., Bibb R., Identifying the geometric constraints and process specific challenges of selective laser melting, In Proceedings of Time Compression Technologies Rapid Manufacturing Conference, Coventry, United Kingdom, 2008.
27. 27. Over C., Generative Fertigung von Bauteilen aus Werkzeugstahl X38CrMoV5-1 und Titan TiAl6V4 mitSelective Laser Melting, PhD Thesis, RWTH Aachen, 2003.
28. 28. Gonzalez J.A., Mireles J., Stafford S.W., Perez M.A., Terrazas C.A., Wicker R.B., Characterization of Inconel 625 Fabricated Using Powder-Bed-Based Additive Manufacturing Technologies, Journal of Materials Processing Technology, https://doi.org/10.1016/j.jmatprotec.2018.08.031
29. 29. EOS material datasheet for Nickel Alloy IN625.