Ikiz Merdane Sürekli Döküm 8006 Alüminyum Alaşımlarının Korozyon Davranışına Soğuk Hadde Ezme Oranının Etkisi
Öz
gibi harika özelliklerinden dolayı, otomotiv sektöründe kullanımı son yıllarda
önemli bir yer tutmaktadır. Özellikle ısı eşanjörü (heat exchanger) elemanı
olarak 3003, 8006 grubu hadde alüminyum alaşımlarının kullanımı, eşanjörlerin
korozif bir sıvı ortamı içermesinden dolayı ve bu malzemelerin korozyon
özelliklerinden dolayı tercih edilmektedir. Bu çalışmada, ikiz
merdane sürekli döküm yöntemi ile elde edilen 8006 grubu alüminyum
alaşımlarının korozyon özelliklerine soğuk haddeleme ezme oranının etkisi
incelenmiştir. 8006 Alüminyum alaşımı, öncelikle soğuk deformasyon haddesi olan
ikiz merdanelerin arasına 8.5 mm kalınlıkta levha olarak döküldü ve
ardından 550 ila 600 oC arasında homojenleştirme tavlamasına
tabi tutuldu. Hemen ardından ezme oranı farklı olan iki haddeleme işlemine tabi
tutularak sırasıyla, %94 ve %98 oranında bir ezme işlemi uygulandı. Nihai
olarak, 400 oC ila 450 oC arasında bir sıcaklıkta normalizasyon tavlamasına
maruz bırakıldı. Elde edilen numunelerin yüzeyi, 1 M NaCI + .H2O2
içeren çözeltide korozyon testleri (açık devre potansiyeli ölçümü ve
polarizasyon eğrileri eldesi) öncesi ve sonrası, stereo mikroskop ile yüzey
görünümü analizine tabi tutuldu ardından 3B yüzey pürüzlülük ölçümü yöntemi
kullanılarak, yüzey pürüzlülüğü analizi gerçekleştirildi. Elde edilen sonuçlara
göre, soğuk deformasyon işlemine bağlı olarak uygulanan farklı ezme oranındaki
artışın ikiz merdane sürekli döküm yöntemi ile elde edilen 8006 alüminyum
alaşımlarının korozyon davranışında azalmaya bağlı olarak, korozyon direncinin
arttığını göstermiştir.
Anahtar Kelimeler
İkiz merdane sürekli döküm alüminyum korozyon polarizasyon eğrileri Soğuk deformasyon ezme oranı 8006
Kaynakça
- [1]. Liu B., Zhang X., Zhou X., Hashimoto T., Wang J., The Corrosion Behaviour of Machined AA7150-T651 Aluminium Alloy, Corrosion Science, 126 (2017) 265-271.
- [2]. Wang J., Zhou X., Thompson G.E., Hunter J.A., Yuan Y., Near-Surface Microstructure on Twin-Roll Cast 8906 Aluminum Alloy, Metallurgical and Materials Transactions, A 46-6 (2015) 2688-2695.
- [3]. Wang J., Zhou X., Thompson G.E., Hunter J.A., Yuan Y., Microstructure Evolution in the Near-Surface Region During Homogenization of a Twin-Roll Cast AlFeMnSi Alloy, Metallurgical and Materials Transactions, A 47-8 (2016) 4268-4275.
- [4]. Imamura T., Shingaki Y., Hayakawa Y., Effect of Cold Rolling Reduction Rate on Secondary Recrystallized Texture in 3 Pct Si-Fe Steel, Metallurgical and materials transactions, A 44-4 (2013) 1785-1792.
- [5]. Georgiou E., Celis J.-P., Panagopoulos C., The Effect of Cold Rolling on the Hydrogen Susceptibility of 5083 Aluminum Alloy, Metals, 7-11 (2017) 451.
- [6]. Delijić K., Markoli B., Naglič I., The Influence of the Chemical Composition on the Corrosion Performances of Some Al-Fe-Si, Al-Mg-Si and Al-Mg-Mn Type of Alloys, Metallurgical and Materials Engineering, 20-4 (2014) 217-234.
- [7]. Ramirez A.H., Ramirez C.H., Costa I., Cold Rolling Effect on the Microstructure and Pitting Resistance of the NBr ISO 5832-1 Austenitic Stainless Steel, International Journal of Electrochemical Science, 8-12 (2013) 12801-12815.
- [8]. Le H., Sutcliffe M., Analysis of Surface Roughness of Cold-Rolled Aluminium Foil, Wear, 244-1 (2000) 71-78.
- [9]. Sanders R.E., Continuous Casting for Aluminum Sheet: a Product Perspective, JOM, 64-2 (2012) 291-301.
- [10]. Birol F., Birol Y., Corrosion of Twin Belt and Twin Roll Cast AlMg3Mn Alloys, Corrosion Engineering, Science and Technology, 49-3 (2014) 228-235.
- [11]. Kikkawa T., New Rolling Method of Reversing Cold Rolling Mill, Proc. AISTech, 2012 (2012) 1771-1780.
- [12]. Rahimi M., Fojan P., Gurevich L., Afshari A., Aluminium Alloy 8011: Surface Characteristics, Applied Mechanics and Materials, Trans Tech Publ, 2015, pp. 29-37.
- [13]. Karlík M., Siegl J., Slámová M., Birol Y., Study of the Damage of AA 8006 Twin-roll Cast Thin Sheets During Forming of Heat Exchanger Fins, Materials Science Forum, Trans Tech Publ, 2000, pp. 619-624.
- [14]. Kurt K., Dursun A., Dilsizoğlu B., Anger G., Ürgen M., Comparison of the Corrosion Behaviors of Twin-Roll Cast and DC Cast AA 6016 and AA6082 for Automotive Applications, TMS, 2006.
- [15]. Cieslar M., Poková M., Annealing Effects in Twin-Roll Cast AA8006 Aluminium Sheets Processed by Accumulative Roll-Bonding, Materials, 7-12 (2014) 8058-8069.
- [16]. [Trakov M.V.I.K.L., Mechanical and Corrosion Properties of AA8011 Sheets And Foils, Materiali in Tehnologije, 40-3 (2006) 83-88.
- [17]. Valjema A.U.M.D., Analysis of Twin-Roll Casting AA8079 Alloy 6.35-μm Foil Rolling Process, Analysis, 50-6 (2016) 861- 868.
- [18]. Nisancioglu K., Holtan H., Measurement of the Critical Pitting Potential of Aluminium, Corrosion Science, 18-9 (1978) 835-849.
- [19]. Standards A.S.T.M., ASTM G69-12, Standard Test Method for Measurement of Corrosion Potentials of Aluminum Alloys, Philadephia, 2003.
Effect of Cold Rolling Reduction Rate on Corrosion Behaviour of Twin-roll Cast 8006 Aluminium Alloys
Öz
Utilization of aluminum alloys in automotive industry takes a crucial role in recent years due to their excellent properties such as corrosion resistance and light weight. 3003 and 8006 aluminum alloys have been particularly used as a heat exchanger compartment due to their corrosion resistance feature which has a perfect match for a heat exchanger fin stocks and a destructive salty environment in this car’s part. In the present work, an effect of cold rolling reduction (CRR) rate on the corrosion twin-roll cast 8006 aluminium alloys was investigated. Firstly, the aluminium alloy was submitted to twin-roll casting process to achieve 8.5 mm thickness sheet. Then, homogenization annealing was applied between 550 °C and 600 °C. Subsequently, two cold rolling routes were subjected at different CRR rates of %94 and %98 respectively. Finally, the aluminium sheets were annealed between 400 °C and 450 °C for 60 min in a furnace for electrochemical corrosion tests. Electrochemical corrosion tests were performed in 1 M NaCl and H2O2 solution, and open circuit potential and polarization curves were successfully achieved. The surface features of the specimens before and after corrosion tests were assessed using stereomicroscopy and 3D profilometer. Based on the results, an increase in the various CRR rates depending on cold rolling route applied decreases the corrosion resistance of the twin-roll cast 8006 aluminum alloys and thus, they could be very versatile materials for heat exchanger fin stock materials.
Anahtar Kelimeler
Twin-roll cast aluminium 8006 corrosion polarization curves cold rolling reduction rate
Kaynakça
- [1]. Liu B., Zhang X., Zhou X., Hashimoto T., Wang J., The Corrosion Behaviour of Machined AA7150-T651 Aluminium Alloy, Corrosion Science, 126 (2017) 265-271.
- [2]. Wang J., Zhou X., Thompson G.E., Hunter J.A., Yuan Y., Near-Surface Microstructure on Twin-Roll Cast 8906 Aluminum Alloy, Metallurgical and Materials Transactions, A 46-6 (2015) 2688-2695.
- [3]. Wang J., Zhou X., Thompson G.E., Hunter J.A., Yuan Y., Microstructure Evolution in the Near-Surface Region During Homogenization of a Twin-Roll Cast AlFeMnSi Alloy, Metallurgical and Materials Transactions, A 47-8 (2016) 4268-4275.
- [4]. Imamura T., Shingaki Y., Hayakawa Y., Effect of Cold Rolling Reduction Rate on Secondary Recrystallized Texture in 3 Pct Si-Fe Steel, Metallurgical and materials transactions, A 44-4 (2013) 1785-1792.
- [5]. Georgiou E., Celis J.-P., Panagopoulos C., The Effect of Cold Rolling on the Hydrogen Susceptibility of 5083 Aluminum Alloy, Metals, 7-11 (2017) 451.
- [6]. Delijić K., Markoli B., Naglič I., The Influence of the Chemical Composition on the Corrosion Performances of Some Al-Fe-Si, Al-Mg-Si and Al-Mg-Mn Type of Alloys, Metallurgical and Materials Engineering, 20-4 (2014) 217-234.
- [7]. Ramirez A.H., Ramirez C.H., Costa I., Cold Rolling Effect on the Microstructure and Pitting Resistance of the NBr ISO 5832-1 Austenitic Stainless Steel, International Journal of Electrochemical Science, 8-12 (2013) 12801-12815.
- [8]. Le H., Sutcliffe M., Analysis of Surface Roughness of Cold-Rolled Aluminium Foil, Wear, 244-1 (2000) 71-78.
- [9]. Sanders R.E., Continuous Casting for Aluminum Sheet: a Product Perspective, JOM, 64-2 (2012) 291-301.
- [10]. Birol F., Birol Y., Corrosion of Twin Belt and Twin Roll Cast AlMg3Mn Alloys, Corrosion Engineering, Science and Technology, 49-3 (2014) 228-235.
- [11]. Kikkawa T., New Rolling Method of Reversing Cold Rolling Mill, Proc. AISTech, 2012 (2012) 1771-1780.
- [12]. Rahimi M., Fojan P., Gurevich L., Afshari A., Aluminium Alloy 8011: Surface Characteristics, Applied Mechanics and Materials, Trans Tech Publ, 2015, pp. 29-37.
- [13]. Karlík M., Siegl J., Slámová M., Birol Y., Study of the Damage of AA 8006 Twin-roll Cast Thin Sheets During Forming of Heat Exchanger Fins, Materials Science Forum, Trans Tech Publ, 2000, pp. 619-624.
- [14]. Kurt K., Dursun A., Dilsizoğlu B., Anger G., Ürgen M., Comparison of the Corrosion Behaviors of Twin-Roll Cast and DC Cast AA 6016 and AA6082 for Automotive Applications, TMS, 2006.
- [15]. Cieslar M., Poková M., Annealing Effects in Twin-Roll Cast AA8006 Aluminium Sheets Processed by Accumulative Roll-Bonding, Materials, 7-12 (2014) 8058-8069.
- [16]. [Trakov M.V.I.K.L., Mechanical and Corrosion Properties of AA8011 Sheets And Foils, Materiali in Tehnologije, 40-3 (2006) 83-88.
- [17]. Valjema A.U.M.D., Analysis of Twin-Roll Casting AA8079 Alloy 6.35-μm Foil Rolling Process, Analysis, 50-6 (2016) 861- 868.
- [18]. Nisancioglu K., Holtan H., Measurement of the Critical Pitting Potential of Aluminium, Corrosion Science, 18-9 (1978) 835-849.
- [19]. Standards A.S.T.M., ASTM G69-12, Standard Test Method for Measurement of Corrosion Potentials of Aluminum Alloys, Philadephia, 2003.
Ayrıntılar
| Birincil Dil | İngilizce |
|---|---|
| Bölüm | Engineering Sciences |
| Yazarlar | |
| Yayımlanma Tarihi | 16 Mart 2018 |
| Gönderilme Tarihi | 5 Şubat 2018 |
| Kabul Tarihi | 14 Mart 2018 |
| Yayımlandığı Sayı | Yıl 2018Cilt: 39 Sayı: 1 |
