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Microstructure and properties of high-conductivity, super-high-strength Cu–8.0Ni–1.8Si–0.6Sn–0.15Mg alloy

Published online by Cambridge University Press:  31 January 2011

Z. Li*
Affiliation:
School of Materials Science and Engineering, Central South University, Changsha 410083, China; and Key Laboratory of Nonferrous Metal Materials Science and Engineering, Ministry of Education, Changsha 410083, China
Z.Y. Pan
Affiliation:
School of Materials Science and Engineering, Central South University, Changsha 410083, China
Y.Y. Zhao
Affiliation:
Department of Engineering, University of Liverpool, Liverpool L69 3GH, United Kingdom
M.P. Wang
Affiliation:
School of Materials Science and Engineering, Central South University, Changsha 410083, China
*
a) Address all correspondence to this author. e-mail: lizhou6931@163.com
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Abstract

A high-conductivity and super-high-strength alloy, Cu-8.0Ni-1.8Si-0.6Sn-0.15Mg, has been developed. The processing conditions of the alloy have been investigated. The evolution of microstructure of the alloy on aging has been examined by transmission electron microscopy. The processing condition giving the highest hardness and good electrical conductivity is as follows: solution treatment at 970 °C for 4 h, cold rolling to 60% reduction, and aging at 500 °C for 30 min. The processed alloy has an average tensile strength of 1180 MPa, 0.2% proof strength of 795 MPa, elongation of 2.75%, and average electrical conductivity of 26.5% IACS. Orthorhombic Ni2Si precipitates are responsible for the age-hardening effect. The orientation relationship between the precipitates and the matrix is (110)m(211)p and. DO22 ordering together with spinodal decomposition also contributed to the hardening.

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Articles
Copyright
Copyright © Materials Research Society 2009

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