Lazerle metal toz ergitme prosesinde kalıntı gerilmelerin mikro girinti tekniği ile incelenmesi

Yıl 2021, Cilt: 36 Sayı: 2, 1029 - 1040, 05.03.2021

Evren Yasa , Özgür Poyraz

https://doi.org/10.17341/gazimmfd.792584

Öz

Toz yatağında lazerle eklemeli (katmanlı) imalat ile metal malzemeden fonksiyonel parça üretimi yaygınlaşmakta ve geniş malzeme spektrumu sayesinde çok sayıda endüstri tarafından tercih edilmektedir. Bununla beraber konvansiyonel imalat yöntemlerine göre daha az olgunlaşmış olan Lazerle Metal Toz Ergitme (LAM) prosesi açısından aşılması gereken bazı kısıtlamalar söz konusudur. Yüksek ergime-katılaşma hızına sahip prosesteki temel problemlerden biri kalıntı (artık) gerilmelerdir. Farklı sayıdaki kalıntı gerilme ölçüm yöntemleri arasında, mikro girinti tekniği yeni yatırım ihtiyacı olmaması açısından avantajlıdır. Bu makalede LAM prosesi ile üretilmiş, bir nikel süperalaşımı olan ve havacılıkta yaygın olarak kullanılan Inconel 625 malzemedeki kalıntı gerilmeleri mikro girinti tekniği ile tespit edilmiştir. Elde edilen değerlerin, literatürde aynı teknik ile incelenmiş diğer nikel süperalaşımlarla uyumlu olduğu görülmüştür.

Anahtar Kelimeler

Toz yatağında lazerle eklemeli (katmanlı) imalat, Inconel 625, Kalıntı gerilmeler, Mikro girinti

INVESTIGATION OF RESIDUAL STRESSES BY MICRO INDENTATION IN SELECTIVE LASER MELTING

Öz

Selective Laser Melting (SLM) of functional parts production from metals are becoming widespread and are preferred by many industries thanks to their wide material portfolio. However, there are still challenges that need to be overcome for the emerging SLM process which is relatively immature in comparison to conventional manufacturing methods. One of the main challenges for the process is the high melting-solidification rate resulting in residual stresses. Among the different number of residual stress measurement techniques, micro indentation has the advantage of not requiring new investments. In this article, residual stresses of SLMed Inconel 625, which is a nickel superalloy widely used in aerospace, were investigated by the micro indentation technique. The values obtained were found to be compatible with other nickel superalloy studies available in the literature.

Anahtar Kelimeler

Laser powder bed fusion, Inconel 625, Residual stresses, Micro indentation

Kaynakça

• 1. ASTM, I. ASTM F2792-10: Standard terminology for additive manufacturing Technologies, ASTM International, 2010.
• 2. Yasa, E., Kruth, J. P., Microstructural investigation of Selective Laser Melting 316L stainless steel parts exposed to laser re-melting, Procedia Engineering, 19, 389-395, 2011.
• 3. Poyraz, O., Kushan, 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), 699-711, 2018
• 4. Kandil, F. A., Lord, J. D., Fry, A. T., Grant, P. V., A Review of Residual Stress Measurement Methods, Measurement of Residual Stress in Components, NPL Report, UK, 2002.
• 5. Rossini, N. S., Dassisti, M., Benyounis, K. Y. Olabi, A. G., Methods of measuring residual stresses in components, Materials & Design, 35, 572-588, 2012.
• 6. Evans, E. B., Residual stresses in processing, Encyclopedia of Materials Science & Engineering, 6, 4183-4188, 1986.
• 7. Littmann, W. E., Measurement and significance of residual macrostress in steel, SAE 793A, Proc. of the Automatic Eng. Cong, 13-17, 1964.
• 8. Poyraz, Ö., Kuşhan, M. C., Residual Stress-induced Distortions in Laser Powder Bed Additive Manufacturing of Nickel-based Superalloys, StrojniskiVestnik/Journal of Mechanical Engineering, 65(6), 2019.
• 9. Kruth, J. P., Deckers, J., Yasa, E., Wauthlé, R., Assessing and comparing influencing factors of residual stresses in selective laser melting using a novel analysis method, Proceedings of the institution of mechanical engineers, Part B: Journal of Engineering Manufacture, 226(6), 980-991, 2012.
• 10. Guo, J., Fu, H., Pan, B., Kang, R., Recent Progress of Residual Stress Measurement Methods: A Review, Chinese Journal of Aeronautics, 2019.
• 11. Yiğit, O., Dilmeç, M., Halkacı, S., Tabaka kaldırma yöntemi ile kalıntı gerilmelerin ölçülmesi ve diğer yöntemlerle karşılaştırılması, Mühendis ve Makine, 49(579), 20-27, 2008
• 12. Kuşhan, M. C., Poyraz, Ö., Uzunonat, Y., Orak, S., Systematical Review On The Numerical Simulations Of Laser Powder Bed Additive Manufacturing, Sigma: Journal of Engineering & Natural Sciences/Mühendislik ve Fen Bilimleri Dergisi, 36(4), 2018
• 13. Wang, X., Chou, Y. K., A method to estimate residual stress in metal parts made by Selective Laser Melting, In ASME 2015 international mechanical engineering congress and exposition, American Society of Mechanical Engineers Digital Collection, 2015.
• 14. Tandon, R., Indentation Based Techniques to Measure Residual Stresses in Engineering Ceramics, (No. SAND2013-4342C), Sandia National Lab.(SNL-NM), Albuquerque, NM (United States), 2013.
• 15. Larsson, P. L., On the influence of elastic deformation for residual stress determination by sharp indentation testing, Journal of Materials Engineering and Performance, 26(8), 3854-3860, 2017.
• 16. Ahn, H. J., Kim, J. H., Xu, H., Lee, J., Kim, J. Y., Kim, Y. C., Kwon, D., Directionality of residual stress evaluated by instrumented indentation testing using wedge indenter, Metals and Materials International, 23(3), 465-472, 2017.
• 17. Pham, T. H., Kim, S. E., Determination of equi-biaxial residual stress and plastic properties in structural steel using instrumented indentation, Materials Science and Engineering: A, 688, 352-363, 2017.
• 18. Breumier, S., Villani, A., Maurice, C., Lévesque, M., Kermouche, G., Effect of crystal orientation on indentation-induced residual stress field: Simulation and experimental validation, Materials & Design, 169, 107659, 2019.
• 19. Zhang, T., Guo, J., Wang, W., A strain-pattern-based spherical indentation method for simultaneous uniaxial tensile residual stress and flow property determination, The Journal of Strain Analysis for Engineering Design, 0309324720921305, 2020.
• 20. EOS material datasheet for Nickel Alloy IN625.
• 21. Broitman, E., Indentation hardness measurements at macro-, micro-, and nanoscale: a critical overview, Tribology Letters, 65(1), 23, 2017.
• 22. Tsui, T. Y., Oliver, W. C., Pharr, G. M., Influences of stress on the measurement of mechanical properties using nanoindentation: Part I. Experimental studies in an aluminum alloy,” Journal of Materials Research, 11(3), 752-759, 1996.
• 23. Johnson, K. L., The correlation of indentation experiments, Journal of the Mechanics and Physics of Solids, 18(2), 115-126, 1970.
• 24. Tabor, D., The physical meaning of indentation and scratch hardness, British Journal of Applied Physics 7.5 (1956): 159, 1956.
• 25. Carlsson, S., Larsson, P. L., On the determination of residual stress and strain fields by sharp indentation testing.: Part I: theoretical and numerical analysis, Acta Materialia, 49(12), 2179-2191, 2001.
• 26. Carlsson, S., and Larsson, P. L. On the determination of residual stress and strain fields by sharp indentation testing.: Part II: experimental investigation, Acta Materialia, 49(12), 2193-2203, 2001.
• 27. Johnson, K. L., The correlation of indentation experiments. Journal of the Mechanics and Physics of Solids,” 18(2), 115-126, 1970.
• 28. Mercelis, P., Kruth, J. P., Residual stresses in selective laser sintering and selective laser melting, Rapid prototyping journal, 2006.
• 29. An, K., Yuan, L., Dial, L.,Spinelli, I., Stoica, A. D., Gao, Y., Neutron residual stress measurement and numerical modeling in a curved thin-walled structure by laser powder bed fusion additive manufacturing, Materials & design, 135, 122-132, 2017.