EFFECT OF CRYOGENIC AND NATURAL AGING PROCESS APPLIED TO Al-Zn-Mg-Cu ALLOYS ON LIFE TIME CALCULATION
Received: 19th June 2023; Revised: 29th June 2023, 12th October 2023, 25th October 2023; Accepted: 31st October 2023
DOI:
https://doi.org/10.20319/mijst.2023.9.113126Keywords:
Al-Zn-Mg-Cu Alloy, Cryogenic Treatment, Natural Aging, Life Time CalculationAbstract
In this study, life time calculation of aluminum 7075 alloy with cryogenic and natural aging processes was performed by thermal analysis. The aluminum alloy was quenched after solid solution treatment at 480°C and naturally aged for 10-100 days at room temperature (25°C). Other samples were cryogenically treated at -40°C and -80°C for 2 hours after solid solution treatment at 480°C. After the cryogenic treatment, natural aging was done at room temperature for 10-100 days. At the end of each period determined for the samples, the hardness values were measured. It was observed that there was no significant change in hardness values at the end of 10 and 100 days at -80 °C. Thus, it was determined that the natural aging process does not start after cryogenic treatment at -80 °C. It was observed that the hardness value of naturally aged samples after cryogenic treatment at -40 °C increased more than the natural aged samples only. This showed that -40 °C improved the mechanism by creating a driving force in the material. Life time calculations between 30 °C and 320 °C also showed that -40 °C cryogenic treatment + natural aging increased life time by approximately 20% compared to natural aging alone.
References
Altuntaş, G., Altuntaş, O., & Bostan, B. (2021). Characterization of Al-7075/T651 Alloy by RRA Heat Treatment and Different Pre-deformation Effects. Transactions of the Indian Institute of Metals, 74, 3025-3033. https://doi.org/10.1007/s12666-021-02369-5
Altuntaş, G., Bostan, B. (2022). Metallurgical characterization of natural aging effects on pre-deformed Al 7075/T651 alloy during retrogression and re-aging heat treatment. Kovove Materialy, 60(4) https://doi.org/10.31577/km.2022.4.209
Altuntaş, G., & Bostan, B. (2021). Al–Zn–Mg–Cu Alaşımının Kristalografisine RRA Isıl İşlemi Etkilerinin İncelenmesi. Politeknik Dergisi, 25(2), 871-877. https://doi.org/10.2339/politeknik.919492
Altuntaş, G., & Bostan, B. (2022) 7075 Al Alaşımına Uygulanan Kriyojenik ve Doğal Yaşlandırma İşleminin Avrami Parametresine Etkisi. Gazi University Journal of Science Part C: Design and Technology, 10(4), 691-698. https://doi.org/10.29109/gujsc.1179514
Chen, J., Zhen, L., Yang, S., Shao, W., & Dai, S. (2009). Investigation of precipitation behavior and related hardening in AA 7055 aluminum alloy. Materials Science and Engineering: A, 500(1-2), 34-42. https://doi.org/10.1016/j.msea.2008.09.065
Couturier, L., Deschamps, A., De Geuser, F., Fazeli, F., & Poole, W. J. (2017). An investigation of the strain dependence of dynamic precipitation in an Al-Zn-Mg-Cu alloy. Scripta Materialia, 136, 120-123. https://doi.org/10.1016/j.scriptamat.2017.04.031
Khalfallah, A., Raho, A. A., Amzert, S., & Djemli, A. (2019). Precipitation kinetics of GP zones, metastable η′ phase, and equilibrium η phase in Al− 5.46 wt. % Zn− 1.67 wt. % Mg alloy. Transactions of Nonferrous Metals Society of China, 29(2), 233-241. https://doi.org/10.1016/S1003-6326(19)64932-0
Lendvai, J. (1996). Precipitation and strengthening in aluminum alloys. In Materials Science Forum (Vol. 217, pp. 43-56). Trans Tech Publications Ltd. https://doi.org/10.4028/www.scientific.net/MSF.217-222.43
Leyva-González, K. A., Deaquino-Lara, R., Pourjafari, D., Martínez-Sánchez, R., Hernandez-Rodriguez, M. A. L., & García-Sánchez, E. (2015). Calorimetry study of the precipitation in an Al7075-graphite composite fabricated by mechanical alloying and hot extrusion. Journal of Thermal Analysis and Calorimetry, 121, 589-595. https://doi.org/10.1007/s10973-015-4581-5
Li, X. Z., Hansen, V., Gjønnes, J., & Wallenberg, L. R. (1999). HREM study and structure modeling of the η′ phase, the hardening precipitates in commercial Al–Zn–Mg alloys. Acta materialia, 47(9), 2651-2659. https://doi.org/10.1016/S1359-6454(99)00138-X
Liu, S., Li, C., Han, S., Deng, Y., & Zhang, X. (2015). Effect of natural aging on quench-induced inhomogeneity of microstructure and hardness in high strength 7055 aluminum alloy. Journal of alloys and compounds, 625, 34-43. https://doi.org/10.1016/j.jallcom.2014.10.195
Mackenzie, D. S., & Totten, G. E. (Eds.). (2003). Handbook of aluminum. New York: Dekker. https://doi.org/10.1201/9780429223259-10
Mukhopadhyay, A. K., & Prasad, K. S. (2011). Formation of plate-shaped Guinier–Preston zones
during natural aging of an Al–Zn–Mg–Cu–Zr alloy. Philosophical magazine letters, 91(3),
-222. https://doi.org/10.1080/09500839.2010.547525
Sha, G., & Cerezo, A. (2004). Early-stage precipitation in Al–Zn–Mg–Cu alloy (7050). Acta materialia, 52(15), 4503-4516. https://doi.org/10.1016/j.actamat.2004.06.025
Wang, J., Chen, X., Yang, L., & Zhang, G. (2022). Effect of preheat & post-weld heat treatment on the microstructure and mechanical properties of 6061-T6 aluminum alloy welded sheets. Materials Science and Engineering: A, 841, 143081. https://doi.org/10.1016/j.msea.2022.143081
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2023 Gözde Altuntaş, Onur Altuntaş, Bülent Bostan
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Copyright of Published Articles
Author(s) retain the article copyright and publishing rights without any restrictions.
All published work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
