Журналы →  Non-ferrous Metals →  2022 →  №2 →  Назад

Название Physical and mechanical properties of ultrapure copper obtained by zone melting
DOI 10.17580/nfm.2022.02.04
Автор Dosmukhamedov N. K., Fedorov A. N., Zholdasbay E. E., Icheva Yu. B.
Информация об авторе

Satbayev University, Almaty, Kazakhstan:

N. K. Dosmukhamedov*, Professor, Department of “Metallurgy and Mineral Processing”, e-mail: nurdos@bk.ru


National University of Science and Technology MISiS, Moscow, Russia:

A. N. Fedorov (1951–2021), Professor, Department of “Non-Ferrous Metals and Gold”


Zhezkazgan University named after O. A. Baikonurov, Zhezkazgan, Kazakhstan:

E. E. Zholdasbay, Associated Professor, Head of Department of “Mining, Metallurgy and Natural Sciences”
Yu. B. Icheva, Associated Professor, Head of Department of “Mining, Metallurgy and Natural Sciences” 


*Correspondence author.


This paper presents the results of studies on the electrical conductivity, macro- and microstructure of ultrapure copper (5N3) obtained after zone melting of refined copper (99.96% Cu). The effect of residual concentrations of impurity metals on the electrical conductivity of ultrapure copper has been established. To assess the effect of low concentration impurities on the electrical conductivity of copper, the authors used a linear dependence of the increase in resistivity on the concentration of impurities (Ci), which was determined by the Mathyssen-Fleming rule. It is shown that low residual concentrations of impurity metals obtained in copper after its zone melting refining, ppm (ppm = 10–4 %): 0.2As; 0.06Sb; 0.006Ag; 0.07Bi; 0.006Sn; 0.02Pb; 1,1Ni have practically no effect on the electrical conductivity of ultrapure copper. The maximum electrical conductivity of M00K industrial grade copper (99.99% Cu) is 59 MSm/m, while zonerefined copper with a copper content of 99.999% has the electrical conductivity of 60.2 MSm/m. The values of the electrical conductivity of the obtained samples can serve to control the quality of obtained copper. It is shown that, in contrast to the microstructure of the initial copper sample, the ultrapure copper microstructure is a densely packed structure consisting of fine grains. On the microstructure map of ultrapure copper, the presence of individual impurity metals in the form of rounded small balls was established. Elongated filaments in the form of continuous lines, which are associated with the formation of chemical compounds of impurity metals with each other, are also found. This phenomenon is clearly observed on the microstructure map of ultrapure copper, captured at a magnification of 1000x under conditions of etching of the sample under study. The values of macro- and microhardness of the initial copper sample and ultrapure copper sample are established. The hardness of the initial copper sample is 84.42 HB (according to Brinell). After zone melting refining of copper from impurities, the hardness of the resulting ultrapure copper was 59.85 HB. Measurements of the microhardness of samples of the initial copper sample and ultrapure copper obtained by zone melting showed the microhardness of 103.0 and 70.42, respectively.

Ключевые слова Electrical conductivity of copper, microanalysis, microstructure, hardness, microhardness, impurities, original sample, ultrapure copper
Библиографический список

1. Valiev R. Z., Aleksandrov I. V. Bulk Nanostructured Metallic Materials: Obtaining, Structure and Properties. Moscow : Akademkniga, 2007. 398 p.
2. Tyumentsev A. N., Pinzhin Yu. P., Ditenberg I. A., Korotaev A. D., Valiev R. Z. Microstructure and Mechanisms of its Formation in Submicrocrystalline Copper Produced by Severe Plastic Deformation. The Physics of Metals and Metallography. 2003. Vol. 96, Iss. 4. pp. 33–43.
3. Yang-Il Jung, Jung-Suk Lee, Jeong-Yong Park, Yong-Hwan Jeong, Kyoung-Seok Moon, Kyoung-Sun Kim. Effect of Ion-Beam Assisted Deposition on Resistivity and Crystallographic Structure of Cr/Cu. Electronic Materials Letters. 2009. Vol. 5, Iss. 3. pp. 105–107.
4. Kurosaka A., Tanabe N., Kohno O., Osanai H. High Purity Copper Wires. Proceedings of Ultra High Purity Base Metals (UHPM-94), Kitakyusyu Fukuoka Japan, May 1994. p. 446.
5. Dost S., Liu Y. C., Haas J., Roszmann J., Grenier S., Audet N. Effect of Applied Electric Current on Impurity Transport in Zone Refining. Journal of Crystal Growth. 2007. Vol. 307, Iss. 1. pp. 211–218.
6. Cheung, T., Cheung N., Garcia A. Application of an Artificial Intelligence Technique to Improve Purification in the Zone Refining Process. Journal of Electronic Materials. 2010. Vol. 39, Iss. 1. pp. 49–55.
7. Zhu Y., Mimura K., Ishikawa Y., Isshiki M. Effect of Floating Zone Refining under Reduced Hydrogen Pressure on Copper Purification. Materials Transactions. 2002. Vol. 43, Iss. 11. pp. 2802–2807.
8. Lalev G. M., Lim J.-W., Munirathnam N. R., Choi G.-S., Uchikoshi M., Mimura K., Isshiki M. Impurity Behavior in Cu Refined by Ar Plasma-Arc Zone Melting. Metals and Materials International. 2009. Vol. 15, Iss. 5. pp. 753–757.
9. Yoon Y. O., Jo H. H., Cho H., Kim S. K., Kim Y. J. Effect of Distribution Coefficient in Copper Purification by Zone Refining Process. Materials Science Forum. 2004. Vol. 449-452. pp. 173–176.
10. Lim J-W., Kim M. S., Munirathnam N. R., Le M. T., Uchikoshi M., Mimura K., Isshiki М., Kwon Н. С. Choi G. S. Effect of Ar/Ar-H2 Plasma Arc Melting on Cu Purification. Materials Transactions. 2008. Vol. 49, Iss. 8. pp. 1826–1829.
11. Cheung T., Cheung N., Tobar C. M. T., Caram R., Gar cia A. Application of a Genetic Algorithm to Optimize Purification in the Zone Refining Process. Materials and Manufacturing Processes. 2011. Vol. 26, Iss. 3. pp. 493–500.
12. Ghosh K., Mani V. N., Dhar S. A Modeling Approach for the Purification of Group III Metals (Ga and In) by Zone Refining. Journal of Applied Physics. Vol. 104, Iss. 2. p. 024904.
13. Alieva Z., Trubitsyn Yu. Vertical Crucibleless Melting Kinetics Management Aspects During Silicon Cleaning. Novye Materialy v Metallurgii i Mashinooborudovanii. 2011. No. 1. pp. 106–110.
14. Liu D., Engelhardt H., Li X., Loffler A., Rettenmayr M. Growth of an Oriented Bi40–xInx n Te 60 (x = 3, 7) Thermoelectric Material by Seeding Zone Melting for the Enhancement of Chemical Homogeneity. CrystEngComm. 2015. Vol. 17, Iss. 16. pp. 3076–3081.
15. Dosmukhamedov N. K., Zholdasbay E. E., Nurlan G. B., Kurmanseitov M. B. Employment of Zone Melting to Obtain Ultrapure Copper: Behavioural Patterns of Impurity Metals. Tsvetnye Metally. 2017. No. 7. pp. 34–40. DOI: 10.17580/tsm.2017.07.06
16. Dosmukhamedov N. K., Zholdasbay E. E., Nurlan G. B. Ultra-Pure Cu Obtaining Using Zone Melting: Influence of Liquid Zone Width on Impurities’ Behavior. Non-Ferrous Metals. 2017. No. 2. pp. 15–20. DOI: 10.17580/nfm.2017.02.03
17. Osintsev O. E., Fedorov V. N. Copper and Copper Alloys. Domestic and Foreign Brands: a Reference Guide. Moscow: Mashinostroeniye, 2004. 336 p.
18. Dorofeev A. L., Rozhkov V. I. Non-Destructive Physical Methods of Hardness Measurement. Moscow: Mashinostroeniye, 1979. 59 p.

Полный текст статьи Physical and mechanical properties of ultrapure copper obtained by zone melting