Effects of Cold Rolling and Aging Treatment on the Properties of Cu-Be Alloy

M. I. Mohamed

Abstract


The effects of precipitated phases during aging treatment on the properties of the Cu-Be alloy have been extensively studied. In this study, the effect of cold rolling on the precipitated phases of the Cu-Be alloy compared with non-deformed alloy during isothermal and low heating rate aging of 20C/min have been investigated. Hardness changes, differential scanning calorimetry (DSC), dilatation analysis, and transmission electron microscopy (TEM) were used in this study. Hardening and contraction were strongly increased at an early aging time for the cold rolled Cu-Be alloy. In addition, the DSC curves revealed an exothermic peak from the γ΄΄ phase. This peak increased and shifted to lower aging time by increasing the cold rolling reduction. In addition, the hardness remarkably increased at lower aging temperatures for the cold rolled specimens. The contraction from the dilatation curves and the exothermic peaks shifted to lower aging temperatures in cold rolled specimens. The hardening of Cu-Be alloy is believed to be from the γ΄ phase, and the contraction and the first exothermic peak in DSC curves from γ΄΄ phase. TEM observations are in a good agreement with the above explanation and strongly revealed that γ΄΄ and γ΄ phases were highly accelerated by the effect of cold rolling


Keywords


precipitation hardening; transmission electron microscopy;- age hardening; solution treatment; cold rolling

Full Text:

PDF

References


E. Rocha-Rangel, J. A. Rodrguez-Garcia, C. A. Hernandez-Bocanegra, “Precipitation hardening of Cu-Be alloys”, ChemXpress Vol. 5 No. 4, pp. 132-136, 2014

M. Mankani, S. S. Sharma, “Heat treatment of mill-hardened beryllium copper for space applications”, Universal Journal of Mechanical Engineering, Vol. 3, No. 4, pp. 147-150, 2015

Z. Zhu, Y. Cai, K. Song, Y. Zhou, J. Zou, “Precipitation Characteristics of the Metastable γ″ Phase in a Cu-Ni-Be Alloy”, Materials, Vol. 11, No. 8, Article ID 1394, 2018

T. Tang, Y. L. Kang, L. J. Yue, X. L. Jiao, “Precipitation behavior of Cu-1.9Be-0.3Ni-0.15Co alloy during aging”, Acta Metallurgica Sinica (English Letters), Vol. 28, No. 3, pp. 307-315, 2015

Y. Tang, Y. Kang, L. Yue, X. Jiao, “Mechanical properties optimization of a Cu–Be–Co–Ni alloy by precipitation design”, Journal of Alloys and Compounds, Vol. 695, pp. 613-625, 2017

Y. Tang, Y. Kang, L. Dejia, M. Shen, Y. Hu, L. Zhao, “Tuning Low Cycle Fatigue Properties of Cu-Be-Co-Ni Alloy by Precipitation Design”, Metals-Open Access Metallurgy Journal, Vol. 8, Article ID 444, 2018

S. Montecinos, S. Tognana, W. Salgueiro, “Influence of microstructure on the Young's modulus in a Cu-2Be (wt.%) alloy”, Journal of Alloys and Compounds, Vol. 729, pp. 43-48, 2017

L. Yagmur, O. Duygulu, B. Aydemir, “Investigation of metastable γ΄ precipitate using HRTEM in aged Cu–Be alloy”, Materials Science and Engineering A, Vol. 528, No. 12, pp. 4147-4151, 2011

W. Bonfield, B. C. Edwards, “Precipitation hardening in Cu 1.81 wt % Be 0.28 wt % Co”, Journal of Materials Science, Vol. 9, No. 3, pp. 398-408, 1974

I. M. Masoud, K. Naito, H. Era, K. Kishitake, “A Shape Memory Behavior Newely Reveled in Cu-Be Alloy”, 7th Cairo University International MDP Conference, Cairo, Egypt, February 15-17, 2000

L. Yang, F. Y. Zhang, M. F. Yan, M. L. Zhang, “Microstructure and mechanical properties of multiphase layer formed during thermo-diffusing of titanium into the surface of C17200 copper-beryllium alloy”, Applied Surface Science, Vol. 292, No. 1, pp. 225-230, 2014

K. Esmati, H. Omidvar, J. Jelokhani, M. Naderi, “Study on the microstructure and mechanical properties of diffusion brazing joint of C17200 copper beryllium alloy“, Materials & Design, Vol. 53, pp. 766-773, 2014

A. Khodabakhshi, V. Abouei, N. Mortazavi, S. H. Razavi, H. Hooshyar, M. Esmaily, “Effects of cold working and heat treatment on microstructure and wear behaviour of Cu–Be alloy C1720”, Tribology-Materials, Surfaces & Interfaces, Vol. 9, No. 3, pp. 118-127, 2015

R. Monzen, S. Okawara, C. Watanable, “Stress-assisted nucleation and growth of γ″ and γ′ precipitates in a Cu–1.2 wt %Be–0.1 wt%Co alloy aged at 320°C”, Philosophical Magazine, Vol. 92, No. 14, pp. 1826-1843, 2012

R. J. Price, A. Kelly, “Deformation of age hardened crystals of copper-1.8 wt.% beryllium”, Acta Metallurgica, Vol. 11, No. 8, pp. 915-922, 1963

W. Ozgowicz, E. Kalinowska-Ozgowicz, B. Grzegorczyk, “Thermomechanical treatment of low-alloy copper alloys of the kind CuCo2Be and CuCo1NiBe”, Journal of Achevements in Materials and Manfacturing Engineering, Vol. 46, No. 2, pp. 161-168, 2011

R. O. Galicia, C. G. Garcia, M. A. Alcantara, A. H. Vazquez, “Influence of Heat Treatment and Composition Variations on Microstructure, Hardness, and Wear Resistance of C18000 Copper Alloy”, ISRN Mechanical Engineering, Vol. 2012, Article ID 248989, 2012

Y. Lim, K. Lee, S. Moon, “Effects of a Post-Weld Heat Treatment on the Mechanical Properties and Microstructure of a Friction-Stir-Welded Beryllium-Copper Alloy”, Metals-Open Access Metallurgy Journal, Vol. 9, No. 4, Article ID 461, 2019

M. Hariram, D. Theerath, P. Chakravarthy, R. A. Kumar, “Influence of cold work on aging response of C17200-beryllium copper alloy C17200”, Materials Today: Proceedings, Vol. 4, No. 10, pp. 11188–11193, 2017




eISSN: 1792-8036     pISSN: 2241-4487