Öz
Metallerin mekanik özellikleri ısıl işlem uygulanması ile artırılabilmektedir. Alüminyum ve alaşımlarının sertlik dayanımlarını arttırabilmek için yaşlandırma işlemi uygulanabilmektedir. Bu çalışmada da 7075 alüminyum alaşımına retrogresyon ve yeniden yaşlandırma işlemi uygulanmıştır. Uygun çözeltiye alma ve suni olarak yaşlandırma işlemi olan T6 ısıl işleminin gerçekleştirildiğinden emin olmak için öncelikle 7075 alüminyum alaşım 480˚C’de 2 saat çözeltide bekletilerek ardından soğutulup, oda sıcaklığında doğal olarak yaşlandırılmıştır. T6 ısıl işlemini ve sonrasında T6 işleminden daha yüksek 150˚C -170˚C -190˚C sıcaklıkları arasında 60 dakika, 180 dakika ve 300 dakika sürelerde yaşlandırma uygulanmıştır. Yaşlandırma sürecinde yeniden çözeltiye alma süresi ve sıcaklıklarını değiştirerek bu değerlerin AA7075 alüminyum alaşımının sertlik değerlerine etkisi araştırılmıştır. Çalışma sonuçları, çözeltiye alma sıcaklığının ve süresinin alüminyum alaşımının sertlik değerinde artış sağladığını göstermiştir. Isıl işlemin sıcaklık ve bekletme süresi, alüminyum alaşımlarının mikroyapısında meydana getirdiği değişikliklerden dolayı alaşımların sertlik değerlerini etkilemektedir.
Anahtar Kelimeler
Alüminyum alaşım 7075 çözeltiye alma ve yaşlandırma sertlik T6 ısıl işlem
Kaynakça
- Ashrafizadeh, S. M., Eivani, A. R., Jafarian, H. R., Zhou, J. (2017). Improvement of mechanical properties of AA6063 aluminum alloy after equal channel angular pressing by applying a two-stage solution treatment. Materials Science & Engineering A, 27, 54–62.
- Aydın, H., Tunçel, O. (2019). AA7075 Alüminyum alaşımında çözme tavı sıcaklığının yaşlanma davranışına etkisi. Uludağ Üniversitesi Mühendislik Fakültesi Dergisi, 24(1), 317-330.
- Cheng, S., Zhao, Zhu, Y. T., Ma, E. (2007). Optimizing the strength and ductility of fine structured 2024 Al alloy by nano-precipitation. Acta Materialia, 55(17), 5822–5832.
- Clark, R., Coughran, B., Traina, I., Hernandez, A., Scheck, T., Etuk, C. (2005). On the correlation of mechanical and physical properties of 7075-T6 Al alloy. Engineering Failure Analysis, 12, 520–6.
- Heinz, A., Haszler, A., Keidel, C., Moldenhauer, S., Benedictus, R., Miller W. S. (2000). Recent development in aluminium alloys for aerospace applications. Materials Science Engineering A, 280(1), 102-107.
- Jin-feng, L., Peng Z., Chao-xing, L., Zhi-qiang, J., Chen, W., Zheng, Z. (2008). Mechanical properties, corrosion behaviors and microstructures of 7075 aluminium alloy with various aging treatments. Transactions of Nonferrous Metals Society of China, 18, 755-762.
- Kang, U. G., Lee, J. C., Jeong, S. W., Nam, W. J. (2010). The improvement of strength and ductility in ultrafine grained 5052 Al alloy by cryogenic and warm rolling. Journal of Material Science, 45, 4739–4744.
- Ma, W. Y., Wang, B. Y., Yang, L., Tang, X. F., Xiao, W. C. (2015). Influence of solution heat treatment on mechanical response and fracture behaviour of aluminium alloy sheets: an experimental study. Materials & Design, 25, 1119–1126.
- Nageswara rao, P., Jayaganthan, R. (2012). Effects of warm rolling and ageing after cryogenic rolling on mechanical properties and microstructure of Al 6061 alloy. Materials and Design 39, 226–233.
- Ozer, G., Karaaslan, H. (2017). Properties of AA7075 aluminum alloy in aging and retrogression and reaging process. Transactions of Nonferrous Metals Society of China, 27, 2357−2362.
- Rendigs, K. H. (1997). Aluminium structures used in aerospace-status and prospects. Materials Science Forum, 242, 11-24.
- Vishwakarma, D. K., Kumar, N., Padap, A. K. (2017). Modelling and optimization of aging parameters for thermal properties of Al 6082 alloy using response surface methodology. Materials Research Express, 4(4), 046502–046513.
- Williams, J. C., Jr Starke E.A. (2003). Progress in structural materials for aerospace systems. Acta Materials, 51(19), 5775-5799.
- Xu, D. K., Rometscha, P.A., Birbilis, N. (2012). Improved solution treatment for an as-rolled Al-Zn-Mg-Cu alloy. Part II. Microstructure and mechanical properties. Materials Science & Engineering A, 534, 244–252.
- Yan, S. L., Yang, H., Li, H. W., Yao, X. (2016). Variation of strain rate sensitivity of an aluminum alloy in a wide strain rate range: mechanism analysis and modeling, Journal of Alloys and Compounds. 688, 776–786.
- Zhou, P., Songa, Y., Hua, L., Lu, J., Zhang, J., Wang, F. (2019). Mechanical behavior and deformation mechanism of 7075 aluminum alloy under solution induced dynamic strain aging. Materials Science & Engineering A, 759, 498–505.
Öz
Mechanical properties of metals can be advanced by applying heat treatment. Aging can be applied to increase the hardness strength of aluminum and its alloys. In this study, retrogression and reaging process was applied to 7075 aluminum alloys. In order to make sure that the T6 process, which is the heat treatment with appropriate solution and artificial aging process, has been performed or not, the 7075 aluminum alloy samples were first kept in solution at 480˚C for 2 hours, then cooled, and naturally aged at room temperature. T6 heat treatment followed by aging for 60 minutes, 180 minutes and 300 minutes at temperatures between 150 °C-170 °C-190 °C higher than T6 treatment temperatures. The effect of these parameters on the hardness values of 7075 aluminum alloy by changing the resolution treatment time and temperatures in the aging process was investigated. The results of the study showed that the solution treatment temperature and time increased the hardness value of the aluminum alloy. The temperature and holding time of the heat treatment affect the hardness values of the alloys due to the changes they cause in the microstructure of the aluminum alloys.
Anahtar Kelimeler
Aluminium alloy 7075 T6 heat treatment solution treatment and aging hardness
Kaynakça
- Ashrafizadeh, S. M., Eivani, A. R., Jafarian, H. R., Zhou, J. (2017). Improvement of mechanical properties of AA6063 aluminum alloy after equal channel angular pressing by applying a two-stage solution treatment. Materials Science & Engineering A, 27, 54–62.
- Aydın, H., Tunçel, O. (2019). AA7075 Alüminyum alaşımında çözme tavı sıcaklığının yaşlanma davranışına etkisi. Uludağ Üniversitesi Mühendislik Fakültesi Dergisi, 24(1), 317-330.
- Cheng, S., Zhao, Zhu, Y. T., Ma, E. (2007). Optimizing the strength and ductility of fine structured 2024 Al alloy by nano-precipitation. Acta Materialia, 55(17), 5822–5832.
- Clark, R., Coughran, B., Traina, I., Hernandez, A., Scheck, T., Etuk, C. (2005). On the correlation of mechanical and physical properties of 7075-T6 Al alloy. Engineering Failure Analysis, 12, 520–6.
- Heinz, A., Haszler, A., Keidel, C., Moldenhauer, S., Benedictus, R., Miller W. S. (2000). Recent development in aluminium alloys for aerospace applications. Materials Science Engineering A, 280(1), 102-107.
- Jin-feng, L., Peng Z., Chao-xing, L., Zhi-qiang, J., Chen, W., Zheng, Z. (2008). Mechanical properties, corrosion behaviors and microstructures of 7075 aluminium alloy with various aging treatments. Transactions of Nonferrous Metals Society of China, 18, 755-762.
- Kang, U. G., Lee, J. C., Jeong, S. W., Nam, W. J. (2010). The improvement of strength and ductility in ultrafine grained 5052 Al alloy by cryogenic and warm rolling. Journal of Material Science, 45, 4739–4744.
- Ma, W. Y., Wang, B. Y., Yang, L., Tang, X. F., Xiao, W. C. (2015). Influence of solution heat treatment on mechanical response and fracture behaviour of aluminium alloy sheets: an experimental study. Materials & Design, 25, 1119–1126.
- Nageswara rao, P., Jayaganthan, R. (2012). Effects of warm rolling and ageing after cryogenic rolling on mechanical properties and microstructure of Al 6061 alloy. Materials and Design 39, 226–233.
- Ozer, G., Karaaslan, H. (2017). Properties of AA7075 aluminum alloy in aging and retrogression and reaging process. Transactions of Nonferrous Metals Society of China, 27, 2357−2362.
- Rendigs, K. H. (1997). Aluminium structures used in aerospace-status and prospects. Materials Science Forum, 242, 11-24.
- Vishwakarma, D. K., Kumar, N., Padap, A. K. (2017). Modelling and optimization of aging parameters for thermal properties of Al 6082 alloy using response surface methodology. Materials Research Express, 4(4), 046502–046513.
- Williams, J. C., Jr Starke E.A. (2003). Progress in structural materials for aerospace systems. Acta Materials, 51(19), 5775-5799.
- Xu, D. K., Rometscha, P.A., Birbilis, N. (2012). Improved solution treatment for an as-rolled Al-Zn-Mg-Cu alloy. Part II. Microstructure and mechanical properties. Materials Science & Engineering A, 534, 244–252.
- Yan, S. L., Yang, H., Li, H. W., Yao, X. (2016). Variation of strain rate sensitivity of an aluminum alloy in a wide strain rate range: mechanism analysis and modeling, Journal of Alloys and Compounds. 688, 776–786.
- Zhou, P., Songa, Y., Hua, L., Lu, J., Zhang, J., Wang, F. (2019). Mechanical behavior and deformation mechanism of 7075 aluminum alloy under solution induced dynamic strain aging. Materials Science & Engineering A, 759, 498–505.
Ayrıntılar
| Birincil Dil | Türkçe |
|---|---|
| Konular | Makine Mühendisliği |
| Bölüm | Makine Mühendisliği |
| Yazarlar | |
| Yayımlanma Tarihi | 3 Mart 2021 |
| Gönderilme Tarihi | 12 Kasım 2020 |
| Yayımlandığı Sayı | Yıl 2021Cilt: 24 Sayı: 1 |
