Journals →  Tsvetnye Metally →  2018 →  #9 →  Back

METAL PROCESSING
ArticleName Comparison of copper-phosphorus brazing alloys rods obtained by continuous casting and hot extrusion techniques
DOI 10.17580/tsm.2018.09.10
ArticleAuthor Tavolzhanskii S. A., Bazhenov V. E., Pashkov I. N.
ArticleAuthorData

National University of Science and Technology “MISiS”, Moscow, Russia

S. A. Tavolzhanskii, Associate Professor of Foundry Technologies and Material Art Working Department (FT&MAW), e-mail: Stavolj@gmail.com
V. E. Bazhenov, Associate Professor of Foundry Technologies and Material Art Working Department (FT&MAW), e-mail: V.E.Bagenov@gmail.com
I. N. Pashkov, Professor of Foundry Technologies and Material Art Working Department (FT&MAW), e-mail: Pashkov_prof@mail.ru

Abstract

From the 70s of the 20th century the copper-phosphorus brazing alloys are used as replacement for silver bearing brazing alloys for high-temperature brazing of pure copper and copper alloys. In Russian Federation the most popular brazing alloys are PMF7 (Cu7P) and P14 (Cu6P4Sn) which typically used in the form of a 2 mm diameter wire or rods. The disadvantage of copper-phosphorus brazing alloys is their poor workability by standard deformation treatment due to the presence of a significant amount of brittle copper phosphide in the alloy structure. This makes it necessary to search for alternative technology of copper-phosphorus brazing alloys production. One of the possible technologies of wire and rods manufacturing from copper-phosphorus brazing alloys is the continuous casting technique with upward drawing (UPCAST). The mentioned brazing alloys in the world practice are not manufactured by casting. Because of that the investigation of mechanical properties, microstructure and surface quality of hot extruded and casted rods with 2.5 and 3 mm diameter of PMF7 and P14 brazing alloys were carried out. Samples for investigation were produced by “Alarm” company (Moscow). Hot extrusion was carried out on a vertical hydraulic press with a force of 300 tons. Continuous casting was carried out using experimental setup with a servomotor controlled drawing device. It has been established that the brazing alloys rods obtained by continuous casting differ from the extruded rods and have a shiny and less oxidized surface. The mechanical properties of casted rods are lower than extruded one but this is not a limiting factor for their usage. It is shown that the higher mechanical properties of the extruded rods are explained by the transformation of brittle Cu3P matrix to plastic α-Cu matrix during the hot working. The results showed that PMF7 and P14 casted rods with a 2.5 and 3 mm diameter can be used as a replacement of hot extruded brazing alloys for pure copper and copper alloys brazing.

keywords Copper-phosphorus brazing alloy; brazing; upward continuous casting; hot extrusion; die mold, Cu7P; Cu6P4Sn
References

1. Asinovskaya G. A., Gagen-Torn K. V., Ilina I. I. Development and study of copper-phosphorus solder alloy of PMFOTsr grade with improved properties. Proceedings of VNIIavtogenmash. Iss. 21. Moscow : VNIIavtogenmash, 1977. pp. 89 – 95.
2. References book for brazing, edited by I. E. Petrunin. 3rd edition. Moscow: Mashinostroenie, 2003. 480 p.
3. Herriot G., Baudelet B., Jonas J. Superplastic behavior of two-phase Cu – P alloys. Acta Metallurgica. 1976. Vol. 24. pp. 687–694.
4. Takemoto T., Okamoto I., Matsumura J. Phase diagrams of Cu – Ag – P and Cu – Sn – P ternary brazing filler metals — Copper Phosphorus brazing filler metals with low melting temperature. Report II. Transactions of JWRI. 1987. Vol. 16, No. 2. pp. 301–307.
5. Osintsev O. E., Fedorov V. N. Copper and copper alloys. National and foreign grades: references book. 2nd Issue, revised and supplemented. Moscow: Innovatsionnoe mashinostroenie, 2016. 360 p.
6. Zhang G., Zhong S., Cheng Y., Qi B. Compound non-silver copperphosphorus-tin filler metals used for brazing brass/copper. Hanjie Xuebao. Transactions of the China Welding Institution. 2017. Vol. 38, No. 12. pp. 33–36.
7. Sheppard T., Yiu H. L. Microstructure and properties of some extruded copperphosphorus alloys. Metal Science. 1984. Vol. 18. pp. 439–448.
8. Rantanen M. Upward continuous casting technique in the production of nonferrous wires. Wire journal. 1980. Vol. 67, No. 3. pp. 102–104.
9. Schlesinger M. E., King M. J., Sole K. C., Davenport W. G. Extractive metallurgy of copper, fifth edition. Oxford : Elsevier, 2011. 472 p.
10. Tavolzhanskii S. A., Bazhenov V. E., Pashkov I. N. Composition, properties, application, and manufacturing features of binary copper-phosphorus solders. Metallurgist. 2016. Vol. 60, No. 7–8. pp. 750–757.
11. Tavolzhanskiy S. A., Koletvinov K. F. Development and application of method of continuous upward casting of billets of small assortment high-temperature solders. Tsvetnye Metally. 2015. No. 11. pp. 85–89.
12. GOST 860–75. Tin. Technical specification. Introduction 1977-01-01. Moscow : Izdatelstvo standartov, 1977. 11 p.
13. GOST 859–2014. Copper. Grades. Introduction 2015-07-01. Moscow : Standartinform, 2015. 6 p.
14. Yiu H. L., Sheppard T. Deformation of Cu – P alloys at high temperatures. Materials Science and Technology. 1985. Vol. 1. pp. 209–219.
15. Tavolzhanskii S. A., Pashkov I. N., Koletvinov K. F. Developing and using alternative methods of continuous casting to make a narrow range of high-temperature solders. Metallurgist. 2014. Vol. 57, No. 9-10. pp. 944–948.

Language of full-text russian
Full content Buy
Back