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RRA İŞLEMİNDE YENİDEN ÇÖZELTİYE ALMA PARAMETRELERİN 7075 ALÜMİNYUM ALAŞIMLARININ ÇEKME DAYANIMINA ETKİSİ

THE EFFECTS OF RETROGRESSION PARAMETERS IN RRA TREATMENT ON TENSILE STRENGTH OF 7075 ALUMINIUM ALLOYS

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Abstract (2. Language): 
In this study retrogression and re-aging (RRA) treatments has been applied on 7075 aluminium alloys after T6 treatment. The alloys were retrogressed at various temperatures and times in the retrogression stage of RRA treatment. The effects of the parameters mentioned above on tensile strengths and % elongations were investigated. Besides fracture surfaces were examined by scanning electron microscopy (SEM) for determination of the effects of retrogression temperatures and times on fracture mechanism. The alloy retrogressed at 220oC for 60 minutes showed the highest tensile strength values, on the other hand, the lowest elongation values. Strong relationship has been seen between hardness and tensile strength; however, no effective relationship for elongation was available. Retrogression temperatures and times affects on microstructure of the alloys, therefore, it has also great influence on the hardness and tensile strength, elongation and fracture mechanism.
Abstract (Original Language): 
Bu çalışmada 7075 alüminyum alaşımlarına T6 ısıl işlemi ardından yeniden çözeltiye alma ve yeniden yaşlandırma işlemi (RRA) uygulanmıştır. RRA işleminin yeniden çözeltiye alma aşamasında alaşımlar farklı sıcaklık ve sürelerde yeniden çözeltiye alınmıştır. Bahsedilen bu parametrelerin alaşımın çekme dayanımına ve % uzama değerlerine etkisi araştırılmıştır. Ayrıca, kırılma yüzeyleri tarama elektron mikroskobu (SEM) ile incelenerek yeniden çözeltiye alma sıcaklığı ve süresinin kırılma mekanizmasına etkisi belirlenmeye çalışılmıştır. En yüksek çekme dayanımı ve en düşük % uzama değerlerine 220oC’de 60 dakika yeniden çözeltiye alınan ve yeniden sertleştirilen alaşımlar sahiptir. Sertlik değerleri ile çekme dayanımı arasında kuvvetli ilişki görülürken aynı durumun % uzama için geçerli değildir. Yeniden çözeltiye alma sıcaklığı ve süresi alaşımın mikroyapısını değiştirdiğinden alaşımların sertlik, çekme, % uzama değerlerine ve kırılma mekanizmalarını etkilemektedir.
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REFERENCES

References: 

1. Miller, W.S., Zhuang, L., Bottema, J.,
Wittebrood, A.J., Smet, P. De, Harsler, A.,
Vieregge, A., “Recent Development in
Aluminium Alloys for the Automotive
Industry”, Mater. Sci. Eng. A 280, 37–49, 2000.
2. Mondolfo L.F., Aluminum Alloys: Structure
and Properties, Boston 7 Butterworths; 1976.
3. Smith, W.E., Mühendislik Alaşımlarının Yapı
ve Özellikleri, Demir Dışı Alaşımlar, Cilt 2,
çeviri M. Erdoğan, Nobel Dağıtım, 2001.
4. Rendigs K H. “Aluminium Structures Used in
Aerospace-Status and Prospects”, J. Mater. Sci.
Forum, 242: 11-24, 1997.
5. Heinz, A., Haszler, A., Keidel, C., Moldenhauer,
S., Benedictus, R., Miller, W S., “Recent
Development in Aluminium Alloys for
Aerospace Applications”, Mat. Sci. Eng. A.,
280, 102-107, 2000.
6. Yurdakul, M., Özbay, O., İç, Y. T., “Selection
of Aerospace Alumınum Alloys, Journal of the
Faculty of Engineering Architecture of Gazi
University, Vol. 17, No 2, 1-23, 2002.
7. Wu, Y.L., Froes, F. H, Alvarez A., Li C.G,, Liu
J., Microstructure and Properties of a New
Super-High-Strength Al–Zn–Mg–Cu alloy
C912, Mater. Design, 18, 211–215. 1997.
8. Dumont, D., Deschamps, A., Brechet, Y., 2003.
“On the Relationship between Microstructure,
Strength and Toughness in AA7050 Aluminum
Alloy”. Mater. Sci. Eng. A, 356, 326–336.
9. Ferrer, C. P., “Optimizing the Strength and SCC
Resistance of Aluminium Alloys Used for
Refurbishing Aging Aircraft”, U.S.N.A Trident
Scholar project report, 2001.
10. ASM Handbook, Heat Treating, ASM.
International Materials Park, Ohio” vol. 4, 1990.
11. Ferrer, C.P., Koul, M.G., Connolly, B.J., Moran,
A.L., “Improvements in Strength and Stress
Corrosion Cracking Properties in Aluminum
Alloy 7075 via Low-Temperature Retrogression
and Re-Ageing Heat Treatments”, Corrosion 6,
520–528, 2003.
12. Cina, B.M., “Reducing the Susceptibility of
Alloys, Alloys Particularly Aluminium to Stress
Corrosion Cracking”, U.S. Patent, No: 3, 856,
584, Dec. 24, 1974.
13. Park, J.K, Ardell, A.J., “Effect of Retrogression
and Reaging Treatments on the Microstructure
of Al-7075-T651”. Mater. Trans. A, 15, 1531–
1543. 1984.
14. Park J K. “Influence of Retrogression and Re-
Ageing on the Strength and Stress Corrosion
Resistance of Aluminium Alloy 7075-T6”,
Mater. Sci. Eng. A 103 (2): 223-231, 1988
15. Viana F, Pinto AMP, Santos HMC, Lopes AB.,
“Retrogression, Re-Aging of 7075 Aluminium
Alloy: Microstructural Characterization”, J.
Mater. Process. Tech. 92–93, 54–59, 1999.
16. Holt, R.T., Raizenne, M. D., and Wallace, W.,
“RRA Heat Treatment of Large Al 7075-T6
Components”, Technical Report No:
ADP010412, 1999.
17. Kibar, E., 7075 Alüminyum Alaşımlarına
Uygulanan RRA Isıl İşlemlerinin Mikroyapı
ve Mekanik Özelliklerine Etkisi”, Sakarya
Üniversitesi, Fen Bilimleri Enstitüsü, Yüksek
Lisans Tezi, Sakarya, 2010.
18. Yılmaz, R., Özyürek, D., Kibar, E., “The
Effects of Retrogression Parameters on Hardness
and Wear Behaviours of 7075 Aluminium
Alloys”, Journal of the Faculty of Engineering
Architecture of Gazi University in press 2012.
19. Baydogan, M., Cimenoglu, H., Kayalı, E.S.,
RRA Işleminin 7075 Alaşımının Mekanik
Özelliklerine Etkisi, ITÜ Dergisi/d,
Mühendislik, Cilt: 3, Sayı: 6, 108-116, 2004.
20. Islam M.U., Wallace W., “Stress Corrosion-
Crack Growth Behaviour of 7475 T6
Retrogressed and Re-aged Aluminium Alloy”,
Metals Technology, 11, 320-322., 1984
RRA İşleminde Yeniden Çözeltiye Alma Parametrelerin 7075… D. Ozyurek ve Ark.
Gazi Üniv. Müh. Mim. Fak. Der. Cilt 27, No 1, 2012 203
21. Danh, N.C., Rajan, K., and Wallace, W., “A
TEM Study of Microstructural Changes During
Retrogression and Reaging in 7075 Aluminum”,
Metall.Mater.Trans. A14, 9, 1843-1850., 1983.
22. Rajan, J.K., Wallace, W., Beddoes, J.C.,
“Microstructural Study of A High-Strength
Stress-Corrosion Resistant 7075 Aluminum
Alloy”, J. Mater. Sci. 17, 10, 2817-2824, 1982.
23. Li, G. F., Zhang, X. M., Lı, P. H., You J. H.,
“Effects of Retrogression Heating Rate on
Microstructures and Mechanical Properties of
Aluminium Alloy 7050”, Trans. Nonferrous
Met. Soc. China, 20, 935-941, 2010.
24. Marlaud T., Deschamps A., Bley F., Lefebvre
W., Baroux B., “Evolution of Precipitate
Microstructures during the Retrogression, Re-
Aging Heat Treatment of an Al– Zn–Mg–Cu.
Alloy”, Acta Mater. 58, 4814–4826, 2010.
25. Kamp, N., Sinclair, I., Starink, M.J., Toughness-
Strength Relations in the Overaged 7449 Al-
Based Alloy, Metall. Mater. Trans. A, 33, 4,
1125-1136, 2002.
26. Abolhasani, A., Zarei-Hanzaki, H.R., Abedi,
M.R. Rokni, The room temperature mechanical
properties of hot rolled 7075 aluminum alloy,
Mater. Design, 34, 631-636, 2012.
27. Fang, S.F., Wang, M.P., Song, M., “An
Approach for the Aging Process Optimization of
Al–Zn–Mg–Cu Series Alloys”, Mater. Design,
30, 2460–2467, 2009.
28. Oliveira A.F., Barros M.C., Cardoso K.R.,
Travessa D.N., “The Effect of RRA on the
Strength and SCC Resistance on AA7050 and
AA7150 Aluminium Alloys”, Mater. Sci. Eng.
A 379, 321-326, 2004.
29. Delasi R., Adler, P.N., “Calorimetric Studies of
7000 Series Aluminum Alloys: I. Matrix
Precipitation Characterization of 7075”, Metall.
Trans. A, vol. 8A, 1177-1183, 1977.
30. Reda, Y. Abdel-Karim, R., Elmahallawi, I.,
“Improvements in Mechanical and Stress
Corrosion Cracking Properties in Al-Alloy 7075
via Retrogression and Re-aging”, Mater. Sci.
Eng. A 485, 468–475, 2008.
31. Buha J, Lumley RN, Crosky AG. “Secondary
Ageing in an Aluminum Alloy 7050”, Mater.
Sci. Eng. A, 492 1–10, 2008.
32. Meng, C, Long H, Zheng Y. “Study of the
Mechanism of Hardness Change of Al–Zn–Mg
Alloy during Retrogression Re-Aging
Treatments by Small Angle X-Ray Scattering
(SAXS)”, Metall. Mater. Trans. A 28:2067–
2071, 1997.
33. Papazian, J.M., “Differential Scanning
Calorimetry Evaluation of Retrogressed and Re-
Aged Microstructures in Aluminum Alloy
7075”, Mater. Sci. Eng. A 79, 1, 97–104, 1986.
34. Ning, A., Liu, Z., Peng, B., Zeng, S.,
“Redistribution and Re-Precipitation of Solute
Atom During Retrogression and Reaging of Al-
Zn-Mg-Cu Alloys”, Trans. Nonferrous Met.
Soc. China, 17, 1005-1011, 2007.
35. Feng, C., Lui, Z.Y., Ning, A.L., Lui, Y. B., Zeng,
S.M., “Retrogression and Re-Aging Treatment of
A1-9.99YoZn- 1.72% Cu-2.5% Mg-O. 13% Zr
aluminum Alloy”, Trans. Nonferrous Met. Soc.
China, 16, 1163-1170, 2006.
36. Baldantoni, A., “On the Microstructural Changes
during the Retrogression and Re-aging of 7075
Type Aluminum Alloys", Mater. Sci. Eng. 72,
L5-L8, 1985.
37. Li, Z. H , Xiong, B., Zhang, Y., Zhu, B.H.,
Wang, F., Liu, H., “Ageing Behavior of an Al-
Zn-Mg-Cu Alloy Pre-Stretched Thick Plate”, J.
Uni. Sci. and Techn. Beijing, 14, 3, 246-250,
2007.
38. Talianker, M., Cina B., “Retrogression and Re-
Aging and the Role of Dislocations in the Stress
Corrosion of 7000-Type Aluminum Alloys”,
Metall. Mater. Trans. A, 20, 2087-2092, 1989.
39. Li, Z., Xiong, B., Zhang, Y., Zhu, B., Wang, F.,
Liu, H., “Investigation on Strength, Toughness
and Microstructure of an Al–Zn–Mg–Cu Alloy
Pre-Stretched Thick Plates in Various Ageing
Tempers”, J. Mater. Process. Tech., 209, 2021–
2027, 2009.

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