Sıcak Presleme Yöntemi ile Üretilen Cu-Cr Alaşımlarının Sertlik ve Elektriksel İletkenlik Özellikleri Üzerine Mekanik Alaşımlama Süresinin Etkisi

Year 2022, Volume: 12 Issue: 1, 47 - 58, 01.06.2022

Hamza Çolak Serhatcan Berk Akçay Temel Varol Onur Güler Hüseyin Can Aksa

Abstract

Yapılan bu çalışmada ağırlıkça %0,5 krom takviyeli bakır partiküllerin mekanik alaşımlama yöntemi ile farklı alaşımlama süreleri
kullanılarak alaşımlandırılması ve üretilen tozların sıcak pres yöntemiyle yoğunlaştırılması çalışmaları yer almaktadır. Mekanik
alaşımlama parametreleri olarak 10:1 bilye:toz oranı, 400 dev/dk dönüş hızı seçilmiştir süreler ise değişken olarak 0, 0,5, 1, 2 ve 4 saat
olacak şekilde belirlenmiştir. Sıcak presleme parametreleri tüm deneylerde sabit olarak kullanılmıştır ve 500 ⁰C ve 600 MPa olarak
belirlenmiştir. Yapılan deneyler neticesinde başlangıçta küresel ve düzensiz morfolojiye sahip tozların 0,5 saat mekanik alaşımlama
işlemi sonrasında pulsu benzeri morfolojiye sahip olduğu belirlenmiştir. Ayrıca yapılan deneyler sonucunda en yüksek spesifik yüzey
alanı 1 saat mekanik alaşımlama işlemi neticesinde elde edilmiştir ve 0,0667 m2/g olarak ölçülmüştür. Bu çalışma kapsamında üretilen
kompakt numunelerin en düşük ve en yüksek sertlik değerleri sırasıyla mekanik alaşımlama işlemi uygulanmamış ve 1 saat mekanik
alaşımlama işlemine tabii tutulmuş numunelere aittir ve 71,97 HB ve 99,12 HB olarak ölçülmüştür. En yüksek elektriksel iletkenlik
değeri de 4 saat mekanik alaşımlama işlemine tabii tutulmuş numuneye aittir ve 91,27 %IACS olarak ölçülmüştür. Yapılan bu çalışma
ile mekanik alaşımlama işlem parametrelerinden biri olan sürenin parçacıkların morfolojisi ve boyutu ile kompakt malzemenin
mikroyapısı ve fiziksel ve mekanik özellikleri üzerine etkileri belirlenmiştir.

Keywords

Bakır, Krom, Mekanik Alaşımlama, Sıcak Presleme, Toz Metalurjisi

Thanks

Bu çalışmanın yazarlarından Hamza ÇOLAK, Yükseköğretim Kurulu tarafından desteklenen 100/2000 YÖK programında doktora bursiyeri olarak desteklenmektedir. Yazarlar, desteklerinden dolayı Yükseköğretim Kurulu 100/2000 YÖK programına teşekkür eder.

The Effect of Mechanical Alloying Time on the Hardness and Electrical Conductivity Properties of Cu-Cr Alloys Produced by Hot Pressing Method

Abstract

This study concentrated on alloying 0.5% chromium reinforced copper particles by weight by mechanical alloying method according
to different alloying times and intensifying the produced powders by hot press method. 10:1 ball:powder ratio and 400 rpm rotation
speed were selected as mechanical alloying parameters and the times were determined as 0, 0.5, 1, 2 and 4 hours as variable. Hot
pressing parameters were used as constant in all experiments and were determined as 500 ⁰C and 600 MPa. As a result of the
experiments, it was determined that the powders with initially spherical and irregular morphology had a flake-like morphology after
0.5 hours of mechanical alloying. In addition, as a result of the experiments, the highest specific surface area was obtained after 1 hour
of mechanical alloying and was measured as 0.0667 m2/g. The lowest and highest hardness values of the compact samples produced
within the scope of this study belong to the samples that were not mechanically alloyed and subjected to 1 hour mechanical alloying,
respectively, and were measured as 71.97 HB and 99.12 HB. The highest electrical conductivity value belongs to the sample subjected
to mechanical alloying process for 4 hours and it was measured as 91.27% IACS. In this study, the effects of time, which is one of the
mechanical alloying process parameters, on the morphology and size of the particles, the microstructure and physical and mechanical
properties of the compact material were determined.

Keywords

Copper, Chromium, Mechanical Alloying, Hot-Pressing, Powder Metallurgy

References

• Baksan, B., Celikyurek, I., Torun, O. 2020. Secondary Aging Effects in Copper-Chromium Alloy. The Eurasia Proceedings of Science Technology Engineering and Mathematics, 11:154-158.
• Braunovic, M., Konchits, V.V., & Myshkin, N.K. 2007. Electrical Contacts: Fundamentals, Applications and Technology (1st ed.). CRC Press. https://dois.org/10.1201/9780849391088
• Çanakçı, A., Çuvalcı, H., Varol, T., Erdemir, F., Özkaya, S., Yalçın E.D. 2014. Microstructure and Abrasive Wear Behavior of CuSn10–Graphite Composites Produced by Powder Metallurgy. Powder Metallurgy and Metal Ceramics. 53:275-287. https://doi.org/10.1007/s11106-014-9614-2.
• Chapman, D. 2015. Copper in Electrical Contacts, Copper Development Association Publication No:223, 4-20. Fang, Q. ve Kang, Z. 2015. An investigation on morphology and structure of Cu–Cr alloy powders prepared by mechanical milling and alloying. Powder Technology, 270:104-111.
• Gale, W.F. ve Totemeier, T.C. 2003. Smithells metals reference book. Elsevier, pp. 1097-1098.
• Gao, N., Huttunen-Saarivirta, E., Tiainen, T. ve Hemmilä, M. 2003. Influence of prior deformation on the age hardening of a phosphorus-containing Cu–0.61wt.%Cr alloy, Materials Science and Engineering: A, 342,1:270-278.
• Guerrero-Paz, J. 2014. Ductile Powders Mechanically Alloyed in an Effective Way. Advanced Materials Research, 976:119-123. https://doi.org/10.4028/www.scientific.net/AMR.976.119
• Güler, Ö. ve Evin, E. 2009. The investigation of contact performance of oxide reinforced copper composite via mechanical alloying. Journal of Materials Processing Technology, 209,3, 1286-1290.
• Güler, O., Varol, T., Alver, Ü., Çanakçı, A. 2019. The effect of flake-like morphology on the coating properties of silver coated copper particles fabricated by electroless plating. Journal of Alloys and Compounds, 782:679-688. https://doi.org/10.1016/j.jallcom.2018.12.229.
• Güler, O., Varol, T., Alver, Ü., Kaya, G., Yıldız, F. 2021. Microstructure and wear characterization of Al2O3 reinforced silver coated copper matrix composites by electroless plating and hot pressing methods. Materials Today Communications, 27. https://doi.org/10.1016/j.mtcomm.2021:102205.
• Holm, R. 1981. Electric contacts: theory and application.
• Lahiri, I. ve Bhargava, S. 2009. Compaction and sintering response of mechanically alloyed Cu–Cr powder, Powder Technology, 189,3:433-438.
• Mesina, M., de Jong, T., Kattentidt, H. ve Dalmijn, W. 2002. Non-ferrous metals characterisation and identification using an electromagnetic sensor, Proc. R'02 congress; recovery recycling re-integration, Geneva, Switzerland, pp. 335-340.
• Neikov, O.D., Naboychenko, S.S. ve Murashova, I.B. 2019. Handbook of Non-Ferrous Metal Powders (Second Edition), Chapter 19 - Production of Copper and Copper Alloy Powders, O.D. Neikov, S.S. Naboychenko, and N.A. Yefimov editors, Elsevier, Oxford, pp. 571-614.
• Patra, S. ve Mondal, K. 2014. Densification behavior of mechanically milled Cu–8 at% Cr alloy and its mechanical and electrical properties. Progress in Natural Science, 24,6:608-622.
• Rooy, E. ve Linden. 1990. Properties and Selection: Nonferrous Alloys and Special-Purpose Materials. In: ASM Metals Handbook. Ohio, pp. 2372-2373.
• Shen, D., Zhu, Y.J., Yang, X. ve Tong, W.P. 2018. Investigation on the microstructure and properties of Cu-Cr alloy prepared by in-situ synthesis method. Vacuum, 149:207-213.
• Shkodich, N., Rogachev, A., Vadchenko, S., Moskovskikh, D., Sachkova, N., Rouvimov, S., Mukasyan. 2014. Bulk Cu–Cr nanocomposites by high-energy ball milling and spark plasma sintering. Journal of Alloys and Compounds, 617:39-46.
• Slade, P.G. 2017. Electrical contacts: principles and applications, CRC press, pp. 794-835.
• Suryanarayana, C. 2001. Mechanical alloying and milling. Progress in Materials Science, 46,1-2:1-184.
• Varol, T., Aksa, H. C. ve Güler, O. 2020. Katmanlı Parçacıklar Kullanılarak Üretilen Bakır Esaslı Malzemelerin Karakterizasyonu . Karadeniz Fen Bilimleri Dergisi , 10 (2):346-359. https://doi.org/10.31466/kfbd.777263
• Varol, T.(a), Akçay, S. , Güler, O. 2021. Akımsız kaplama yöntemi ile Cu-Ag bimetal parçacıkların üretimi ve karakterizasyonu. Gümüşhane Üniversitesi Fen Bilimleri Enstitüsü Dergisi, 11:586-596.
• Varol, T.(b), Güler, O., Akçay, S.B. ve Aksa, H.C. 2021. The effect of silver coated copper particle content on the properties of novel Cu-Ag alloys prepared by hot pressing method. Powder Technology, 384:236-246.
• Wang, J., Wu, S., Suo, X.-K., and Liao, H. 2019. The Processes for Fabricating Nanopowders. Advanced Nanomaterials and Coatings by Thermal Spray, 13–25. https://doi.org/10.1016/b978-0-12-813870-0.00002-4
• Zhao, Q., Shao, Z., Liu, C.J., Jiang, M.F., Li, X., Zevenhoven, R., and Saxen, H. 2014. Preparation of Cu–Cr alloy powder by mechanical alloying. Journal of Alloys and Compounds. 607:118–124. https://doi.org/10.1016/j.jallcom.2014.04.054.
• Zheng, Z., Li, X.-j., Gang, T. ve Du, C.-X. 2009. CuCr bulk alloy produced by mechanical alloying and explosive compaction. Transactions of Nonferrous Metals Society of China, 19:626-629.
• Zuo, K., XI, S., & Zhou, J. 2009. Effect of temperature on mechanical alloying of Cu-Zn and Cu-Cr system. Transactions of Nonferrous Metals Society of China, 19(5): 1206–1214. https://doi.org/10.1016/s1003-6326(08)60430-6