Doğal Yaşlanmanın Bakır Kaplı Çelik Fren Borularının Mekanik Özellikleri Üzerindeki Etkisi

Abstract

Bakır kaplı çelik borular, özellikle otomobil fren sistemleri olmak üzere birçok ürünün hidrolik sistemlerinin temel bileşenleridir. Otomotiv endüstrisinde kullanılmak üzere üretilen bakır kaplı çelik boruların mekanik özellikleri kabul kriterleri ile belirlenmektedir. Üretimden sonra stok ve transfer sürecinde bu özelliklerini koruması beklenmektedir. Ancak metalik malzemeler uzun süre oda sıcaklığında tutulduğunda doğal yaşlanmaya uğrayabilir. Bu çalışmada, farklı çaplardaki (ø4.75, ø6, ø8 mm) bakır kaplı çelik boruların 1 yıl oda sıcaklığında bekletilerek mekanik özelliklerindeki değişimler incelenmiştir. Mekanik özellikler çekme ve kumlama deneyleri ile karakterize edilmiş ve mekanik özelliklerdeki değişimler optik mikroskop kullanılarak mikro yapısı incelenerek incelenmiştir. Sonuçlar, fren borularının çekme özelliklerinde hafif bir azalma olmasına karşın mikroyapısal olarak önemli bir değişim olmadığını göstermiştir.

Keywords

• Bakır kaplı çelik boru
• mekanik özellikler
• mikro yapı
• doğal yaşlanma.

Effect of Natural Aging on Mechanical Properties of Copper Clad Steel Brake Pipes

Abstract

Copper-clad steel tubes are the basic components of the hydraulic systems of many products, especially automobile brake systems. The mechanical properties of copper-clad steel tubes produced for use in the automotive industry are determined by acceptance criteria. After production, they are expected to maintain these properties during the stock and transfer process. However, metallic materials may undergo natural aging when kept at room temperature for a long time. In this study, the changes in the mechanical properties of copper-clad steel tubes of different diameters (ø4.75, ø6, ø8 mm) were investigated by keeping them at room temperature for 1 year. The mechanical properties were characterized by tensile and blasting tests, and the changes in mechanical properties were investigated by examining the microstructure using an optical microscope. Results showed that the there is no significant microstructural changes while there was a slight decrease in the tensile properties of brake pipes.

Keywords

• Copper-clad steel tube
• mechanical properties
• microstructure
• natural aging.

References

1. [1] D. Nedelcu and I. Carcea, “Technology for obtaining samples of layered composite materials with metallic matrix,” Met. Mater. Int., vol. 19, no. 1, pp. 105–112, 2013.
2. [2] O. Koyuncu, B. Çelik, Y. Akgül, and A. İncesu, “Isıl İşlemin Bakır Kaplı Çelik Boruların Mekanik Özelliklerine Etkisinin Araştırılması,” J. Mater. Mechatron. A, vol. 4, no. 1, pp. 177–192, 2023.
3. [3] D. K. Miner, “Automotive hydraulic brake tube: the case for 90-10 copper-nickel tubing,” in SAE International Congress and Exposition, Detroit, USA, 1993.
4. [4] O. Koyuncu, B. Çelik, Y. Akgül, and A. İncesu, “Farklı Hız ve Sabit Oranda Uygulanan Redüksiyonun Fren Boruların Mekanik Özelliklerine Etkisinin Araştırılması,” Çelik Araşt. Ve Geliştirme Derg., vol. 4, no. 1, pp. 17–23, 2023.
5. [5] E. A. Yakovleva, A. V. Larionov, G. D. Motovilina, and E. I. Khlusova, “Effect of Natural and Artificial Aging on Steel Mechanical Properties and Fracture Toughness,” Inorg. Mater. Appl. Res., vol. 13, no. 6, pp. 1490–1498, 2022.
6. [6] G. Krauss, Steels: Heat Treatment and Processing Principles, 1st ed., Materials Park, OH, USA: ASM International, 1990, pp. 44–50.
7. [7] K. Homma, C. Miki, and H. Yang, “Fracture toughness of cold worked and simulated heat affected structural steel,” Eng. Fract. Mech., vol. 59, no. 1, pp. 17–28, 1998.
8. [8] G. Xu, Y. Yang, and X. Zhang, “Study of aging behavior of CSP hot bands for cold sheets,” Mater. Charact., vol. 59, no. 9, pp. 1355–1358, 2008.

9. [9] T. Trzepieciński and S. M. Najm, “Current trends in metallic materials for body panels and structural members used in the automotive industry,” Materials, vol. 17, no. 3, p. 590, 2024.
10. [10] P. Bałon et al., “A method of manufacturing car mufflers by wrapping sheets, using innovative forming device with the use of servo drive,” Procedia Manuf., vol. 50, pp. 17–21, 2020.
11. [11] O. Koyuncu, B. Çelik, Y. Akgül, and A. İncesu, “Aynı Sıcaklıkta Uygulanan Isıl İşlem ve Farklı Oranda Uygulanan Redüksiyon İşleminin Fren Borularına Mekanik Özelliklerine Etkisinin Araştırılması,” Çelik Araşt. Ve Geliştirme Derg., vol. 5, no. 1, pp. 1–8, 2024.
12. [12] N. E. González-Arévalo et al., “Influence of aging steel on pipeline burst pressure prediction and its impact on failure probability estimation,” Eng. Fail. Anal., vol. 120, p. 104950, 2021.
13. [13] G. Li, L. Ke, W. Peng, X. Ren, and C. Sun, “Effects of natural aging and variable loading on very high cycle fatigue behavior of a bearing steel GCr15,” Theor. Appl. Fract. Mech., vol. 119, p. 103360, 2022.
14. [14] Y. Kawahara et al., “Characterization of age hardening mechanism of low-temperature aged low-carbon steel by transmission electron microscopy,” Mater. Charact., vol. 183, p. 111579, 2022.
15. [15] V. L. Indenbom, “Dislocations and internal stresses,” in Modern Problems in Condensed Matter Sciences, Amsterdam, Netherlands: Elsevier, 1992, ch. 1, pp. 1–174.
16. [16] A. K. De, K. De Blauwe, S. Vandeputte, and B. C. De Cooman, “Effect of dislocation density on the low temperature aging behavior of an ultra low carbon bake hardening steel,” J. Alloys Compd., vol. 310, no. 1–2, pp. 405–410, 2000.
17. [17] M. Zamani, H. Mirzadeh, and M. Maleki, “Enhancement of mechanical properties of low carbon dual phase steel via natural aging,” Mater. Sci. Eng. A, vol. 734, pp. 178–183, 2018.
18. [18] G. Li, J. Liu, J. Sun, and C. Sun, “Effects of Natural Aging and Discontinuous Cyclic Loading on High Cycle Fatigue Behavior of Steels,” Metals, vol. 13, no. 3, p. 511, 2023.
19. [19] T. D. Barlow, “Aging effects on the fatigue performance of deep rolled bar steels,” M.S. thesis, Faculty and Board of Trustees, Colorado School of Mines, Colorado, USA, 2013.
20. [20] F.-C. An, J.-J. Wang, S.-X. Zhao, and C.-M. Liu, “Tailoring cementite precipitation and mechanical properties of quenched and tempered steel by nickel partitioning between cementite and ferrite,” Mater. Sci. Eng. A, vol. 802, p. 140686, 2021.
21. [21] K. Yoshioka, Y. Zhang, G. Lu, A. Bunger, J. Adachi, and B. Bourdin, “Improving the Accuracy of Fracture Toughness Measurement in Burst Experiments,” Rock Mech. Rock Eng., vol. 56, no. 1, pp. 427–436, 2023.