Instability of Plastic Deformation in Low-Alloy Copper Alloys

Abstract:

The purpose of this paper is to determine the influence of temperature of plastic deformation on the structure and mechanical properties of copper alloys of the types CuCo1NiBe (CCNB), CuCo2Be (CB4), CuNi2SiCr (CNCS), CuNi1P (CNP) and CuCr1Zr (CW106C) applied on electrodesduring a tensile test. Tensile tests were carried out on polycrystalline samples of above mentioned alloys, which confirmed the presence of inhomogeneous plastic deformation in specified temperature ranges for each alloy. The tensile test of the investigated copper alloys were realized in the temperature range of 20÷800 °C with strain rate of 1.2•10^-3s^–1 on the universal testing machine. Metallographic observations of the structure were carried out on a light microscope and the fractographic investigation of fracture on an electron scanning microscope. Performed experimental studies have proven that analyzed structural factors, in a range of investigated strain conditions at elevated temperature, significantly influence the phenomenon of the Portevin Le Chatelier (PLC) type instability of plastic strain, revealed in low-alloy copper alloys. Moreover, it was found that the impact of examined factors on the PLC effect should be considered comprehensively, taking into account their synergic interactions.

• Periodical: Solid State Phenomena (Volume 275)
• Pages: 113-123
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.275.113
• Online since: June 2018
• Authors: Barbara Grzegorczyk*
• Keywords: Copper Alloys, Plastic Deformation, PLC Effect, Tensile Test at Elevated Temperature

References

[1] A.H. Cottrell. Dislocations and Plastic Flow in Crystals. Oxford University Press, London, (1953).

[2] A. Portevin. F. Le Chatelier: Sur un phénomène observé lors de l'essai de traction d'alliages en cours de transformation. Comptes Rendus de l'Académie des Sciences Paris T 176, (1923). pp.507-510.

[3] Y. Estrin, L.P. Kubin, Plastic instabilities phenomenology and theory, Materials Science and Engineering, A, 137, 125-134 (1991).

DOI: 10.1016/0921-5093(91)90326-i

[4] Z. Kovács, L. Lendvai, G. Vörös. Localized deformation bands in Portevin–Le Châtelier plastic instabilities at a constant stress rate Materials Science and Engineering A, 279 (1–2) (1997), pp.179-184.

DOI: 10.1016/s0921-5093(99)00628-0

[5] Ndeye Awa Sene Pascale Balland Khaidre Bouabdallah: Experimental study of Portevin–Le Châtelier bands on tensile and plane strain tensile tests. Archives of Civil and Mechanical Engineering Vol.18, Issue 1 (2018) pp.94-102.

DOI: 10.1016/j.acme.2017.05.005

[6] A. Van Den Beukel: On the mechanism of serrated yielding and dynamic strain ageing Acta Metallurgica. Vol. 28, Issue 7. (1980) pp.965-969.

DOI: 10.1016/0001-6160(80)90114-5

[7] A. Korbel: Analysis of heterogeneous deformation phenomena in solutions of substitution, Scientific Papers University. Metallurgy and Foundry, 65 (1974) 9-7. (in Polish).

[8] N. Ranc. D. Wagner: Some aspects of Portevin–Le Chatelier plastic instabilities investigated by infrared pyrometry. Mater. Sci Eng A 394 (2005). p.87–95.

DOI: 10.1016/j.msea.2004.11.042

[9] Z. Kovàcs: PhD.Thesis; Portevin –Le Chatelier plastic instabilities, Eötcös Loránd Univ., Budapest (2002).

[10] W.H. Wang, D. Wu, S.S.A. Shah, R.S. Chen, C.S. Lou. The mechanism of critical strain and serration type of the serrated flow in Mg–Nd–Zn alloy Mater. Sci. Eng. A, 649 (2016), pp.214-221.

DOI: 10.1016/j.msea.2015.09.100

[11] W Ozgowicz. B. Grzegorczyk. A. Pawełek. A. Piatkowski. Z. Ranachowski: The Portevin–Le Chatelier Effect and Acoustic Emission of Plastic Deformation Archives of Metallurgy and Materials 59 (1), (2014). pp.183-188.

DOI: 10.2478/amm-2014-0029

[12] L. Kommel. I. Hussainova. O. Volobueva: Microstructure and properties development of copper during severe plastic deformation. Materials and Design 28 (2007). p.2121–2128.

DOI: 10.1016/j.matdes.2006.05.021

[13] L.P. Kubin. Y. Estrin: Evolution of dislocation densities and the critical condition for the Portevin-LeChatelier effect. Acta Metallurgica 38, (1990) pp.697-708.

DOI: 10.1016/0956-7151(90)90021-8

[14] L.P. Kubin. Y. Estrin: The critical conditions for jerky flow. Phys. Stat. Sol. (b) 172, (1992) s. 173÷185.

DOI: 10.1002/pssb.2221720117

[15] Y. Brechet, Y. Estrin: Pseudo-Portevin-Le Chatelier effect in ordered alloys Scripta Materialia Vol. 35, No.2 (1996) pp.217-223.

DOI: 10.1016/1359-6462(96)00126-1

[16] P.G. McCormick: The effect of strain on the ageing time for serrated yielding in an Al-Mg-Si alloy Acta Metallurgica, Vol. 22, Issue 4, (1974) pp.489-493.

DOI: 10.1016/0001-6160(74)90102-3

[17] B.J Brindley, P.J Worthington: Serrated yielding in Aluminium-3% Magnesium Acta Metallurgica, Vol.17, Issue 11, (1969) pp.1357-1361.

DOI: 10.1016/0001-6160(69)90153-9

[18] B. J. Brindley, P. J. Worthington: Reply to on the grain-size dependence of the activation energy associated with serrated yielding, Scripta Metallurgica, Vol. 4, Issue 4, (1970) pp.295-297.

DOI: 10.1016/0036-9748(70)90124-9

[19] P. Penning: Mathematics of the Portevin- LeChatelier effect, Acta Metall. 20, (1972) p.1169.

[20] R.C. Picu: Mechanism for the strain rate sensitivity of dilute solid solutions, Acta Materiala, (2004) pp.3447-3458.

DOI: 10.1016/j.actamat.2004.03.042

[21] A. Korbel: The structural aspect of the Portevin-Le Chatelier effect in alpha brass Scripta Metallurgica Vol. 8, (1974) pp.609-612.

DOI: 10.1016/0036-9748(74)90004-0

[22] Grzegorczyk, B., Effect of PLC in monocrystalline Cu-Zn alloy plastically deformed et elevated temperature, PhD thesis, Silesian Univ. of Technology, Gliwice, (2010) (in Polish).

[23] W. Ozgowicz. B. Grzegorczyk. E. Kalinowska-Ozgowicz: The influence of the temperature of tensile test on the structure and plastic properties of copper alloy type CuCr1Zr, Journal of Achievements in Materials and Manufacturing Engineering. 29, Issue 2, (2008).

DOI: 10.5604/01.3001.0010.0978

[24] W. Ozgowicz. B. Grzegorczyk. The influence of the temperature of plastic deformation on the structure and mechanical properties of copper alloys CuCo2Be and CuCo1Ni1Be, Archives of Materials Science and Engineering, Volume 39, Issue 1, (2009).

DOI: 10.5604/01.3001.0010.0978

[25] B. Grzegorczyk. W. Ozgowicz: Influence of plastic deformation temperature on the structure and mechanical properties of low-alloy copper alloys with Co, Ni and B. Archives of Materials Science and Engineering 84 (2) (2016) pp.49-57.

DOI: 10.5604/01.3001.0010.0978