İşlem parametrelerinin ve tavlama işleminin PLA numunelerinin mekanik ve yüzey özelliklerine etkisi

Öz

Bağlam— Erimiş Katmanlı Üretim (FDM), ekonomik üretim, geometrik çok yönlülük ve geniş malzeme bulunabilirliği sunduğu için yaygın olarak benimsenen bir eklemeli üretim yöntemi haline gelmiştir. FDM'de kullanılan termoplastikler arasında, çevre dostu yapısı ve elverişli işleme özellikleri nedeniyle polilaktik asit (PLA) yaygın olarak tercih edilmektedir. Bununla birlikte, FDM ile üretilen PLA parçalarının mekanik özellikleri ve yüzey kalitesi, hem üretim parametrelerine hem de işlem sonrası uygulamalara karşı oldukça hassastır. Önceki araştırmalar, katman kalınlığı, dolgu yoğunluğu ve tavlama gibi faktörlerin ayrı ayrı etkilerini raporlamış olsa da, bunların birleşik etkisini sistematik olarak değerlendiren çalışmalar hala azdır. Amaç— Bu araştırma, katman kalınlığı, dolgu yoğunluğu ve tavlama sıcaklığındaki varyasyonların FDM ile üretilen PLA parçalarının çekme performansı ve yüzey özelliklerini nasıl etkilediğini incelemeye odaklanmıştır. Özellikle, çalışma, hangi işleme parametrelerinin çekme dayanımı, elastik modül, uzama, özgül çekme dayanımı ve yüzey pürüzlülüğünü en güçlü şekilde etkilediğini belirlemeyi ve ayrıca basılı PLA parçalarında sertlik ve süneklik arasındaki dengeyi sağlamadaki rollerini açıklamayı amaçlamıştır. Yöntem— Katman kalınlığının 0,12, 0,16 ve 0,20 mm, dolgu yoğunluğunun %20, %40 ve %60 ve tavlama durumlarının (baskı sonrası, 60 °C ve 90 °C) etkisini değerlendirmek için bir L9 Taguchi ortogonal dizisi uygulandı. PLA'dan yapılmış çekme numuneleri, kontrollü işlem koşulları altında FDM tabanlı bir 3D baskı sistemi kullanılarak üretildi. Mekanik karakterizasyon, çekme dayanımı, elastik modül ve uzama değerlerini elde etmek için çekme testi yoluyla gerçekleştirildi; özgül çekme dayanımı ise numune kütle ölçümleri entegre edilerek belirlendi. Yüzey kalitesi, üç boyutlu optik profilometre ile ortalama yüzey pürüzlülüğünün (Ra) ölçülmesiyle değerlendirildi. Seçilen parametrelerin etkileri ve göreceli önemi, sinyal-gürültü oranları ve varyans analizi teknikleri kullanılarak istatistiksel olarak analiz edildi. Sonuçlar— Sonuçlar, dolgu yoğunluğunun çekme dayanımını etkileyen en önemli faktör olduğunu ve katkı oranının %87,76 olduğunu, yaklaşık 43-45 MPa'lık maksimum dayanımların ise %60 dolguda elde edildiğini göstermiştir. Katman kalınlığı, elastik modülü (%48,17) ve uzamayı (%71,64) kontrol eden baskın parametre olarak belirlenmiş ve sertlik-süneklik dengesinde kritik bir rol oynamıştır. Daha kalın katmanlar daha belirgin ve görünür katman basamak yapıları oluşturdukça yüzey pürüzlülüğü artmıştır. Katman kalınlığının yüzey pürüzlülüğü üzerindeki genel etkisi %84,73 olmuştur. Sonuç— Bu çalışma, birden fazla işleme parametresinin PLA bileşenlerinin mekanik davranışını ve yüzey özelliklerini nasıl etkilediğine dair bütünleşik bir değerlendirme sunmaktadır. Sonuçlar, dayanım, süneklik, ağırlık verimliliği ve yüzey kalitesinin optimizasyonunu desteklemekte ve FDM ile üretilen PLA parçalarının mühendislik tasarımı için pratik bilgiler sağlamaktadır.

Anahtar Kelimeler

• FDM
• PLA
• Mekanik özellikler
• Yüzey pürüzlülüğü

Effect of process parameters and annealing treatment on mechanical and surface properties of PLA samples

Abstract

Context— Fused Deposition Modeling (FDM) has become a commonly adopted additive manufacturing method because it offers economical production, geometric versatility, and broad material availability. Among the thermoplastics used in FDM, polylactic acid (PLA) is widely preferred due to its environmentally friendly nature and favorable processing characteristics. Nevertheless, the mechanical properties and surface finish of PLA parts produced by FDM are highly sensitive to both manufacturing parameters and post-processing practices. Although previous research has reported the separate effects of factors such as layer thickness, infill density, and annealing, studies that systematically evaluate their combined impact are still scarce. Objective— This research focused on examining how variations in layer thickness, infill density, and annealing temperature affect the tensile performance and surface characteristics of PLA parts produced by FDM. In particular, the study aimed to determine which processing parameters most strongly influence tensile strength, elastic modulus, elongation, specific tensile strength, and surface roughness, as well as to explain their role in balancing stiffness and ductility in printed PLA parts. Method— An L9 Taguchi orthogonal array was implemented to assess the influence of layer thickness set at 0.12, 0.16, and 0.20 mm, infill density levels of 20, 40, and 60 percent, and annealing states consisting of as-printed, 60 °C, and 90 °C. Tensile samples made of PLA were fabricated using an FDM-based 3D printing system under controlled processing conditions. Mechanical characterization was carried out through tensile testing to obtain tensile strength, elastic modulus, and elongation values, whereas specific tensile strength was determined by incorporating sample mass measurements. Surface quality was evaluated by measuring the average surface roughness (Ra) with a three-dimensional optical profilometer. The effects and relative significance of the selected parameters were statistically analyzed using signal-to-noise ratios and analysis of variance techniques. Results— The results showed that infill density was the most important factor affecting tensile strength, with a contribution ratio of 87.76%, and maximum strengths of approximately 43–45 MPa obtained at 60% infill. Layer thickness was identified as the dominant parameter controlling elastic modulus (48.17%) and elongation (71.64%), its critical role in the stiffness–ductility balance. Surface roughness increased as thicker layers formed more pronounced and visible layer-step structures. Surface roughness increased as thicker layers produced more pronounced and visible layer-step structures. The overall effect of layer thickness on surface roughness was 84.73%. Conclusion— This work presents an integrated assessment of how multiple processing parameters influence the mechanical behavior and surface characteristics of PLA components. The results support the optimization of strength, ductility, weight efficiency, and surface finish, and contribute practical insight for the engineering design of PLA parts manufactured by FDM.

Keywords

• FDM
• PLA
• Mechanical properties
• Surface roughness

Kaynakça

1. [1] Q. Yan, H. Dong, J. Su, J. Han, B. Song, Q. Wei, Y. Shi, “A review of 3D printing technology for medical applications”, Engineering, 4(5), (2018), 729–742.
2. [2] S. Dağlı, “Investigation of the Bonding Performance of Parts Produced by FDM and SLA 3D Printing Methods”, Manufacturing Technologies and Applications, 6(1), (2025), 100–110.
3. [3] M. M. Sofu, H. V. Özkavak, S. Bacak, M. Fenkli, “Comparison of Strength, Surface Quality and Cost of Different Additive Manufacturing Methods”, Manufacturing Technologies and Applications, 4(1), (2023), 25–36.
4. [4] S. C. Joshi, A. A. Sheikh, “3D printing in aerospace and its long-term sustainability”, Virtual and physical prototyping, 10(4), (2015), 175–185.
5. [5] T. Singh, S. Kumar, S. Sehgal, “3D printing of engineering materials: A state of the art review”, Materials today: proceedings, 28, (2020), 1927–1931.
6. [6] A. Aimar, A. Palermo, B. Innocenti, “The role of 3D printing in medical applications: a state of the art”, Journal of healthcare engineering, 2019(1), (2019), 5340616.
7. [7] P. Jain, A. M. Kuthe, “Feasibility study of manufacturing using rapid prototyping: FDM approach”, Procedia Engineering, 63, (2013), 4–11.
8. [8] T. N. A. T. Rahim, A. M. Abdullah, H. Md Akil, “Recent developments in fused deposition modeling-based 3D printing of polymers and their composites”, Polymer Reviews, 59(4), (2019), 589–624.

9. [9] İ. B. Yeter, H. Kenan, C. O. Azeloğlu, “Kafes geometriye sahip sandviç bir yapının mekanik özelliklerinin deneysel ve sayısal analizi”, Pamukkale Üniversitesi Mühendislik Bilimleri Dergisi, 32(1), (2025), 23-34.
10. [10] M. I. Abd El Aal, M. M. Awd Allah, S. A. Abd Alaziz, M. A. Abd El-baky, “Biodegradable 3D printed polylactic acid structures for different engineering applications: effect of infill pattern and density”, Journal of Polymer Research, 31(1), (2024), 4.
11. [11] M. Altuğ, Y. Yılmaz, “Examination of 3D printing parameters using machine learning”, Pamukkale Üniversitesi Mühendislik Bilimleri Dergisi, to be published, doi:10.65206/pajes.91679.
12. [12] İ. B. Toprak, “Eriyik Yığma Modelleme Süreç Parametrelerinin Taguchi Tabanlı Gri İlişkisel Analiz Yöntemi ile Çoklu Yanıt Optimizasyonu”, Manufacturing Technologies and Applications, 5(2), (2024), 89-103.
13. [13] M. M. Prabhakar, A. K. Saravanan, A. H. Lenin, K. Mayandi, P. S. Ramalingam, “A short review on 3D printing methods, process parameters and materials”, Materials Today: Proceedings, 45, (2021), 6108–6114.
14. [14] A. K. Sood, R. K. Ohdar, S. S. Mahapatra, “Experimental investigation and empirical modelling of FDM process for compressive strength improvement”, Journal of Advanced Research, 3(1), (2012), 81–90.
15. [15] Y. Kuruoğlu, M. Akgün, H. Demir, “Analysis and Optimization of Process Parameters Affecting on the Tensile Strength of PLA and Iron-Reinforced PLA Samples Fabricated by Fused Deposition Modeling Method”, Manufacturing Technologies and Applications, 4(2), (2023), 72–80.
16. [16] M. Günay, S. Gündüz, H. Yılmaz, N. Yaşar, R. Kaçar, “PLA esaslı numunelerde çekme dayanımı için 3D baskı işlem parametrelerinin optimizasyonu”, Politeknik Dergisi, 23(1), (2020), 73–79.
17. [17] Q. Guo, J. C. Crittenden, “An energy analysis of polylactic acid (PLA) produced from corn grain and corn stover integrated system”, Proceedings of the 2011 IEEE International Symposium on Sustainable Systems and Technology, Chicago, IL, USA, 16-18 May 2011, 1–5.
18. [18] S. Demir, “3B yazıcı ile Poli laktik asit (PLA) esaslı numune üretiminde yazıcı parametrelerinin sertlik üzerindeki etkisi”, Pamukkale Üniversitesi Mühendislik Bilimleri Dergisi, 30(2), (2024), 136–144.
19. [19] H. T. H. Nguyen, P. Qi, M. Rostagno, A. Feteha, S. A. Miller, “The quest for high glass transition temperature bioplastics”, Journal of Materials Chemistry A, 6(20), (2018), 9298–9331.
20. [20] T. J. Suteja, A. Soesanti, “Mechanical properties of 3D printed polylactic acid product for various infill design parameters: a review”, Journal of Physics: Conference Series, 1569(4), (2020), 042010.
21. [21] K. N. Gunasekaran, V. Aravinth, C. B. M. Kumaran, K. Madhankumar, S. P. Kumar, “Investigation of mechanical properties of PLA printed materials under varying infill density”, Materials Today: Proceedings, 45, (2021), 1849–1856.
22. [22] M. H. Umer, M. B. Khan, M. Q. Zafar, G. Hussain, B. Ashfaq, M. U. Arshad, W. A. Lughmani, “Influence of process parameters on mechanical properties and surface roughness in fused filament fabrication: a comprehensive review”, Journal of the Brazilian Society of Mechanical Sciences and Engineering, 47(6), (2025), 1–29.
23. [23] U. Raza, A. Ahmed, S. Waheed, M. Abid, M. Tahir, A. Zahid, A. Ahmed, M. Bilal, T. Hussain, G. Mustafa, “Recent advancements in fused deposition modeling”, Polymers for Advanced Technologies, 36(1), (2025), e70028.
24. [24] K. Shergill, Y. Chen, S. Bull, “What controls layer thickness effects on the mechanical properties of additive manufactured polymers”, Surface and Coatings Technology, 475, (2023), 130131.
25. [25] D. Syrlybayev, B. Zharylkassyn, A. Seisekulova, M. Akhmetov, A. Perveen, D. Talamona, “Optimisation of strength properties of FDM printed parts—A critical review”, Polymers, 13(10), (2021), 1587.
26. [26] N. Vidakis, C. David, M. Petousis, D. Sagris, N. Mountakis, A. Moutsopoulou, “The effect of six key process control parameters on the surface roughness, dimensional accuracy, and porosity in material extrusion 3D printing of polylactic acid: Prediction models and optimization supported by robust design analysis”, Advances in Industrial and Manufacturing Engineering, 5, (2022), 100104.
27. [27] M. Sharma, V. Sharma, P. Kala, “Optimization of process variables to improve the mechanical properties of FDM structures”, Journal of Physics: Conference Series, 1240(1), (2019), 012061.
28. [28] B. Rankouhi, S. Javadpour, F. Delfanian, T. Letcher, “Failure analysis and mechanical characterization of 3D printed ABS with respect to layer thickness and orientation”, Journal of Failure Analysis and Prevention, 16(3), (2016), 467–481.
29. [29] A. Rodríguez-Panes, J. Claver, A. M. Camacho, “The influence of manufacturing parameters on the mechanical behaviour of PLA and ABS pieces manufactured by FDM: A comparative analysis”, Materials, 11(8), (2018), 1333.
30. [30] W. Kiński, P. Pietkiewicz, “Influence of the print layer height in FDM technology on the rolling force value and the print time”, Agricultural Engineering, 23(4), (2019), 1-9.
31. [31] M. S. Anoop, P. Senthil, “Homogenisation of elastic properties in FDM components using microscale RVE numerical analysis”, Journal of the Brazilian Society of Mechanical Sciences and Engineering, 41(12), (2019), 540.
32. [32] V. S. Jatti, S. V Jatti, A. P. Patel, V. S. Jatti, “A study on effect of fused deposition modeling process parameters on mechanical properties”, International Journal of Scientific & Technology Research, 8(11), (2019), 689–693.
33. [33] S. Garg, A. Singh, Q. Murtaza, “Measuring the Impact of Infill Pattern and Infill Density on the Properties of 3D-Printed PLA via FDM”, Journal of Materials Engineering and Performance, 34, (2025), 22597–22610.
34. [34] S. Santosh, M. S. S. Muthiah, K. S. Nishad, “Influence of infill density on the mechanical properties and fracture behavior of 3D-printed PLA+ components”, Macromolecular Research, 33, (2025), 1407–1420.
35. [35] B. A. Aloyaydi, S. Sivasankaran, H. R. Ammar, “Influence of infill density on microstructure and flexural behavior of 3D printed PLA thermoplastic parts processed by fusion deposition modeling”, AIMS materials science, 6(6), (2019), 1033-1048.
36. [36] M. Ö. Öteyaka, K. Aybar, H. C. Öteyaka, “Effect of infill ratio on the tensile and flexural properties of unreinforced and carbon fiber-reinforced polylactic acid manufactured by fused deposition modeling”, Journal of Materials Engineering and Performance, 30(7), (2021), 5203–5215.
37. [37] P. K. Mishra, P. Senthil, S. Adarsh, M. S. Anoop, “An investigation to study the combined effect of different infill pattern and infill density on the impact strength of 3D printed polylactic acid parts”, Composites Communications, 24, (2021), 100605.
38. [38] M. Vorkapić, I. Mladenović, T. Ivanov, A. Kovačević, M. S. Hasan, A. Simonović, I. Trajković, “Enhancing mechanical properties of 3D printed thermoplastic polymers by annealing in moulds”, Advances in Mechanical Engineering, 14(8), (2022), 16878132221120736.
39. [39] R. A. Wach, P. Wolszczak, A. Adamus‐Wlodarczyk, “Enhancement of mechanical properties of FDM‐PLA parts via thermal annealing”, Macromolecular Materials and Engineering, 303(9), (2018), 1800169.
40. [40] L. Yu, H. Liu, F. Xie, L. Chen, X. Li, “Effect of annealing and orientation on microstructures and mechanical properties of polylactic acid”, Polymer Engineering & Science, 48(4), (2008), 634–641.
41. [41] F. Kartal, A. Kaptan, “Effects of annealing temperature and duration on mechanical properties of PLA plastics produced by 3D Printing”, European Mechanical Science, 7(3), (2023), 152–159.
42. [42] R. V. Pazhamannil, N. Krishnan C, G. P, A. Edacherian, “Investigations into the effect of thermal annealing on fused filament fabrication process”, Advances in Materials and Processing Technologies, 8(2), (2022), 710–723.
43. [43] I. A. Reis, P. I. Cunha Claro, A. L. Marcomini, L. H. Capparelli Mattoso, S. P. da Silva, A. R. de Sena Neto, “Annealing and crystallization kinetics of poly (lactic acid) pieces obtained by additive manufacturing”, Polymer Engineering & Science, 61(7), (2021), 2097–2104.
44. [44] N. Jayanth, K. Jaswanthraj, S. Sandeep, N. H. Mallaya, S. R. Siddharth, “Effect of heat treatment on mechanical properties of 3D printed PLA”, Journal of the Mechanical Behavior of Biomedical Materials, 123, (2021), 104764.
45. [45] H. Kang, Y. Li, M. Gong, Y. Guo, Z. Guo, Q. Fang, X. Li, “An environmentally sustainable plasticizer toughened polylactide”, RSC advances, 8(21), (2018), 11643–11651.
46. [46] S. Singh, A. Rajeshkannan, S. Feroz, A. K. Jeevanantham, “Effect of normalizing on the tensile strength, shrinkage and surface roughness of PLA plastic”, Materials Today: Proceedings, 24, (2020), 1174–1182.
47. [47] H. Gonabadi, A. Yadav, S. J. Bull, “The effect of processing parameters on the mechanical characteristics of PLA produced by a 3D FFF printer”, The International Journal of Advanced Manufacturing Technology, 111(3), (2020), 695–709.
48. [48] Y. Y. Aw, C. K. Yeoh, M. A. Idris, P. L. Teh, K. A. Hamzah, S. A. Sazali, “Effect of printing parameters on tensile, dynamic mechanical, and thermoelectric properties of FDM 3D printed CABS/ZnO composites”, Materials, 11(4), (2018), 466.
49. [49] Y. Zhao, Y. Chen, Y. Zhou, “Novel mechanical models of tensile strength and elastic property of FDM AM PLA materials: Experimental and theoretical analyses”, Materials & Design, 181, (2019), 108089.
50. [50] M. Samykano, S. K. Selvamani, K. Kadirgama, W. K. Ngui, G. Kanagaraj, K. Sudhakar, “Mechanical property of FDM printed ABS: influence of printing parameters”, The International Journal of Advanced Manufacturing Technology, 102(9), (2019), 2779–2796.
51. [51] S. Valvez, A. P. Silva, P. N. B. Reis, F. Berto, “Annealing effect on mechanical properties of 3D printed composites”, Procedia Structural Integrity, 37, (2022), 738–745.
52. [52] X. Zhao, J. Liu, J. Li, X. Liang, W. Zhou, S. Peng, “Strategies and techniques for improving heat resistance and mechanical performances of poly (lactic acid)(PLA) biodegradable materials”, International Journal of Biological Macromolecules, 218, (2022), 115–134.
53. [53] M. Ö. Öteyaka, F. H. Çakir, M. A. Sofuoğlu, “Effect of infill pattern and ratio on the flexural and vibration damping characteristics of FDM printed PLA samples”, Materials Today Communications, 33, (2022), 104912.
54. [54] E. Kaya, İ. Bayar, A. F. Akpınar, “Dolgu desenlerinin ve oranlarının ergiyik biriktirme modellemede PLA malzemesinin mekanik performansına olan etkisi”, Niğde Ömer Halisdemir Üniversitesi Mühendislik Bilimleri Dergisi, 13(3), (2024), 792–798.
55. [55] S. Ekşi, C. Karakaya, “Effects of process parameters on tensile properties of 3D-Printed PLA parts fabricated with the FDM method”, Polymers, 17(14), (2025), 1934.