Emine ALDIRMAZ, Harun CELIK, İlhan AKSOY

Effects of Deformation on Microstructure of Cu-Zn-Ni Alloy

The thermal and mechanical effects on microstructure of Cu-12.44%Zn-4.75%Ni (wt%) alloy were investigated. The effects mechanical on both rapidly cooled sample and slowly cooled sample obtained from Cu-Zn-Ni alloy were investigated by using scanning electron microscopy (SEM), X-ray diffraction techniques (XRD). The thermal energy changes of in the alloy were examined by means of differential scanning calorimetry (DSC). As a result of SEM observations, annealing twins structures are observed in rapidly and slowly cooled samples. According to pictures of the SEM and XRD, the stress applied to samples caused to lose existing annealing twins, and led to formation of slip planes lying parallel to each other in between plates. The stress-strain behaviour is associated with applied heat treatment effect to samples. It’s shown that the intensities of XRD peaks to be decrease, as a result of the increase in cooling rate. This result indicates that density defects of crystal increases with rapidly cooled in the Cu-Zn-Ni alloy. In both samples of the thermal energy changes, at the process of diffusion transformation eutectoid separation reactions have been proved to exist.

Keywords:

Cu-Zn-Ni Alloy Cooling Rate, XRD, Stress-Strain Behaviour.,

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[1] Callister, W. D., “Materials Science and Engineering An Introductions”, John Wiley & Sons, Inc., New York, (1994).
[2] Xie, H., Jia, L., Lu, Z., “Microstructure and solidification behaviour of Cu–Ni–Si alloys” Mater. Charact., 60: 114 (2009).
[3] Peng, M., Mikula,. A., “Thermodynamic properties of liquid Cu-Sn-Zn alloys”, J. Alloy Compd., 247: 185 (1997).
[4] Castro, M. L. and Romero, R., “Optical microscopy of isothermally decomposed β copper based SM alloys” J. Electron Microsc., 216: 1(2004).
[5] Miettinen, J., “Thermodynamic description of the Cu–Ni–Zn system above 600 ◦C”, Calphad, 27: 263 (2003).
[6] Çelik, H., Aldırmaz, E., Sarı U. and Aksoy, Đ., “Effect of cooling rate on stress-strain behaviour and micrustructure of Cu-Zn-Sn alloy”, BPL, 16 (1):161070 (2009).
[7] Hall, O.E., “Twinning and Diffusionless Transformations in Metals” Butterworths Scientific Publications, (1954).
[8] Askeland, D. R., “The Science and Engineering of Materials”, Chapman and Hall, London, (1990).
[9] Xu, J. W., “Effects of Gd addition on microstructure and shape memory effect of Cu– Zn–Al alloy”, J. Alloy Compd., 448: 331 (2008).
[10] Virtanen, P., Tiainen T., and Lepistö, T., “Precipitation at Faceting Grain Boundaries of Cu-Ni-Sn Alloys”, Mat. Sci. Eng. A, 251: 269 (1998).
[11] Rollason, E. C., “Metallurgy for Engineers, 4th edition, Edward Arnold, London, [12] Timings, R. L., “Manufacturing technology”, level 3: Longman, London, (1984).
[13] Cuniberti, A. and Romero, R., “Slip systems in Cu–Zn–Al martensitic phases” Mat. Sci. Eng. A, 273-275 362 (1999).
[14] Dvorak, I. and Hawbolt, E. B., “Transformational Elasticity in a Polycrystalline Cu-Zn-Sn Alloy” Metal. Trans. A, 6A: 95 (1975).
[15] Adachi, K. and Perkins, J., “Deformation of Martensite in a Polycrystalline Cu-Zn-AI Alloy” Metal. Trans. A, 17A 945. (1986).
[16] Sahu, P., Pradhan, S.K. and De, M., “X-ray diffraction studies of the decomposition and microstructural characterization of cold-worked powders of Cu–15Ni–Sn alloys by Rietveld analysis”, J. Alloy Compd., 377 103. (2004).
[17] El-Chiekh, F., El-Haty, M. T., Minoura H. and Montaser, A. A., “Electrodeposition and characterization of Cu–Ni–Zn and Cu–Ni–Cd alloys” Electrochim. Acta., 50: 2857 (2005).
[18] Porter, D.A. and Easterling,, K. E., Pergamon Pres, London, 5, 303 (1989).
[19] Manosa, L., Jurada, M., Alfons, G.-C., Obrado, E., Planes, A., Zarestky, J., Stassis, C., Romero, R., Somazo A. and Morin, M., “A comparative study of the post-quench behaviour of Cu-Al-Be and Cu-Zn-Al shape memory alloys” Acta Mater., 46 1045 (1998).
[20] Kayalı, N., Zengin, R. and Adıgüzel, O., “Influence of Aging on Transformation Characteristics in Shape Memory CuZnAl Alloys” Metall. Mater. Trans. A, 31A: 349 (2000).

Gazi University Journal of Science-Cover

Yayın Aralığı: Yılda 4 Sayı
Başlangıç: 1988
Yayıncı: Gazi Üniversitesi, Fen Bilimleri Enstitüsü

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