The Effects of Zn, Cu and Mg Elements on Ageing, Microstructure and Hardness in Al Alloys Produced by P/M Method

Yıl 2020, Cilt: 8 Sayı: 1, 150 - 159, 23.03.2020

Sinan Aksöz , Hakan Ada , Emre İnce , Serkan Özsoy , Yavuz Kaplan

https://doi.org/10.29109/gujsc.660489

Öz

In this study, two different compositions contain pure Al, Zn, Cu and Mg were produced by powder metallurgy. The powders were pressed under 800 MPa and sintered in purity argon
atmosphere at 600ºC after pressing process. Solution heat treatment were applied to sintered samples at 480ºC and then rapid quenching was performed. For quenched samples; Ageing process was carried out at 120ºC for 3h periods totally 12 hours. As a result, the ageing process leads to increased hardness due to the homogeneously dispersed secondary precipitates that form internally in the microstructure. 

Anahtar Kelimeler

Powder Metallurgy, Ageing, Solution Treating, Al-Zn-Cu-Mg Alloy

T/M Yöntemi ile Üretilen Al Alaşımlarında Zn, Cu ve Mg Elementlerinin, Yaşlanma, Mikroyapı ve Sertliğe Etkileri

Öz

Bu çalışmada, saf haldeki Al, Zn, Cu ve Mg tozlarından mekanik öğütme ile iki farklı kompozisyonda malzeme üretilmiştir. Daha sonra tozlar 800 MPa basınç altında preslenmiş ve presleme sonrası 600ºC’de atmosfer kontrollü fırında (yüksek saflıktaki argon) sinterleme işlemine tabi tutulmuştur. Sinterlenen numunelere 480ºC’de çözündürme işlemi uygulandıktan sonra, hızlı su verme işlemi gerçekleştirilmiştir. Su verilen numunelere ise; 120 ºC yaşlandırma sıcaklığında, 3’er saat arayla, toplamda 12 saat yaşlandırma işlemi uygulanmıştır. Numunelerde yaşlanma ve sinterlemenin etkilerini incelemek için FESEM, Optik Mikroskop, Element Dağılım Spektrometresi, Haritalama (MAP), sertlikteki etkileri incelemek için mikrosertlik ölçümleri gerçekleştirilmiştir. İncelemeler sonucunda yaşlanma sonrası sertlikte artış meydana gelmiş ve sertlikteki bu artışın mikroyapıda içten oluşumlu şekilde meydana gelen çökeltilerin sayesinde olduğu gözlemlenmiştir.

Anahtar Kelimeler

Toz metalürjisi, Yaşlandırma, Çözeltiye Alma, Al 7075

Kaynakça

• 1. Tan E., Aksöz S., Kaplan Y., Can H., Dışpınar D. Improvement in Metallurgical Properties of Gravity Die Cast 2024-T6 Aluminum Alloy via Cryogenic Process. In: Tiryakioğlu M., Griffiths W., Jolly M. (eds) Shape Casting. The Minerals, Metals & Materials Series. Springer, Cham, (2019).
• 2. Aksöz S., Özdemir A.T., Bostan B., “Alloyed AA2014 Alüminium Powders Synthesized with carbon and determined properties”, Journal of the Faculty of Engineering and Architecture of Gazi University, 27 (1):109-115, (2012).
• 3. Aksöz S., Bostan B., “Effects of the AA2014/B4 C MMCs production with casting and post casting sintering operations on wear behaviors”, Journal of Boron, 3 (2) 132-137, (2018).
• 4. Aksöz S., Bostan B., “Effect of ageing and cryo-ageing treatments on microstructure and hardness properties of AA2014-SiC MMCs”, Transactions of the Indian Institute of Metals, 71 (2018) 2035-2042.
• 5. Aksöz S., Özdemir A.T., Çalin R., Altınok Z. and Bostan B., “Effects of sintering, ageing and cryogenic treatments on structural and mechanical properties of AA2014-B4C composite”, J. of the Faculty of Engineering and Architecture of Gazi University, 28 (4) 831-839, (2013).
• 6. Tan E., Kaplan Y., Ada H. and Aksöz S., “Production of the AA2196-TiB2 MMCs via PM Technology”, Chesonis C. (eds), Light Metals. The Minerals, Metals & Materials Series, Springer, Cham. 153-157, (2019).
• 7. Contreras A., Angeles-Chávez C., Flores O., Perez R, “Structural, morphological and interfacial characterization of Al–Mg/TiC composites”, Materials Characterization 58: 685–693 (2007).
• 8. Panigrahi S.K., Jayaganthan R., “Development of ultrafine grained high strength age hardenable Al 7075 alloy by cryorolling”, Materials and Design 32 : 3150-3160, (2011).
• 9. LI Jin – feng, PENG Zhou-wei, LI Chao-xing, JIA Zhi-giang, CHEN Wen – jing, ZHENG Zi-qiano, “Mechanical properties, corrosion behaviors, and micostructures of 7075 aluminium alloy with various aging treatment”, Trans. Nonferrous Met. Soc. Chine 18 :775-762 (2008).
• 10. J Harrison T., R Crawford B., Janardhana M., Clark G., “Differing microstructural properties of 7075-T6sheet and 7075-T651extrudedaluminium alloy”, Procedia Engineering, Vol. 10, 2011, p. 3117–3121, (2011).
• 11. Taşkesen A., Aksöz S., Özdemir A.T., “The effect of cryogenic treatment on ageing behaviour of B4C reinforced 7075 aluminium composites”, Kovove Mater., (55) 57-67, (2017)
• 12. Baradeswaran A., Perumal A.E., “Wear and mechanical characteristics of Al 7075/graphite composites”, Composites: Part B, 54: 146–152, (2013).
• 13. Suryanarayana C., “Mechanical alloying and milling”, Progress in Materials Science 46: 1-184, (2001).
• 14. Baradeswaran A., Elaya Perumal A., “Study on mechanical and wear properties of Al 7075/Al2O3/graphite hybrid composites”, Composites: Part B, 56:464–471, (2014).
• 15. Barbour J.C., Knapp J.A., Follstaedt D.M., Myers S.M., “Process for The Synthesis of Nanophase Dispersion Strengthened Aluminum Alloy”,United States Patent, Patent Number: 5,849,373, Date of Patent: Dec. 15, (1998).
• 16. Heck F.W., Ramsey N.J., Donachie S.J., Windsor N., Merrick H.F., Suffern N.Y., “DİSPERSON STRENGTHENED LOW DENSITY MA-AL” United States Patent, Patent Number: 4,594,222, Date of Patent: Jun. 10, (1986).
• 17. Hoyt J.J., “On the coarsening of precipitates located on grain boundaries and dislocations”, Acta Metallurgica et Materialia, 39: 9, 2091-2098, (1991).
• 18. Enayati M.H., Salehi M., “Formation mechanism of Fe3Al and FeAl intermetallic compounds during mechanical alloying”, Journal of Materials Science 40: 3933 – 3938, (2005).
• 19. Bououdina M., Guo Z.X., “Comparative study of mechanical alloying of (Mg1Al) and (Mg1Al1Ni) mixtures for hydrogen storage” Journal of Alloys and Compounds 336 : 222–231, (2002).
• 20. Yıldırım M., Özyürek D., Gürü M., “The Effects of Precipitate Size on the Hardness and Wear Behaviors of Aged 7075 Aluminum Alloys Produced by Powder Metallurgy Route”, Arab J Sci Eng, 41:4273–4281, (2016).