Enhancing electrical conductivity and strength in Al alloys by modification of conventional thermo-mechanical process

Abstract Although aluminum alloys can be made as excellent conductors, their applications to electrical and electronic industries are often limited because of their relatively low strength. A new strategy of micro-structural design for improving combination of electrical conductivity and strength in Al alloy is developed based on modification of the sequence of conventional cold-deformation and artificial aging. The proposed thermo-mechanical process could enhance the removal of solutes from the Al matrix and properly utilize the work-hardening effect to compensate the loss of age-hardening effect due to the coarsening of the hardening precipitates in the material, such that an excellent combination of good electrical conductivity and enhanced strength as well as reasonable ductility can be achieved in an Al–Mg–Si–(Cu) alloy. The featured microstructure of the alloy was examined in order to understand the obtained properties of the material.

[1]  F. Zhao,et al.  Effect of annealing treatment on the microstructure and mechanical properties of ultrafine-grained aluminum , 2014 .

[2]  R. R. Gibbon,et al.  Overhead transmission lines-refurbishment and developments , 1994 .

[3]  Sedat Karabay,et al.  Modification of AA-6201 alloy for manufacturing of high conductivity and extra high conductivity wires with property of high tensile stress after artificial aging heat treatment for all-aluminium alloy conductors , 2006 .

[4]  J. Robson,et al.  The formation of nanograin structures and accelerated room-temperature theta precipitation in a severely deformed Al–4 wt.% Cu alloy , 2010 .

[5]  Jihua Chen,et al.  A tuning nano-precipitation approach for achieving enhanced strength and good ductility in Al alloys , 2014 .

[6]  David Reay,et al.  Compact and Micro-heat Exchangers , 2013 .

[7]  Kazunari Yoshida,et al.  Improvement of Ductility of Aluminum Wire for Automotive Wiring Harness by Alternate Drawing , 2014 .

[8]  N. Tsuji,et al.  Change in electrical resistivity of commercial purity aluminium severely plastic deformed , 2010 .

[9]  Guoqing Zhang,et al.  Room-temperature workability of 6063 alloy for fitting clamps of overhead conductor lines , 2015 .

[10]  M. V. van Huis,et al.  Atomic Pillar-Based Nanoprecipitates Strengthen AlMgSi Alloys , 2006, Science.

[11]  M. B. Kasen.  Solute segregation and boundary structural change during grain growth , 1983 .

[12]  R. Valiev,et al.  Enhanced mechanical properties and electrical conductivity in ultrafine-grained Al alloy processed via ECAP-PC , 2013, Journal of Materials Science.

[13]  Paul L. Rossiter,et al.  The Electrical Resistivity of Metals and Alloys , 1987 .

[14]  Wang Yunli,et al.  Effect of Cerium on Mechanical Performance and Electrical Conductivity of Aluminum Rod for Electrical Purpose , 2006 .

[15]  Q. Du,et al.  Modeling precipitate growth in multicomponent alloy systems by a variational principle , 2014 .

[16]  Deju Zhu,et al.  Hierarchical nanostructures strengthen Al–Mg–Si alloys processed by deformation and aging , 2013 .

[17]  D. Laughlin,et al.  Phase relations and precipitation in Al–Mg–Si alloys with Cu additions , 2004 .

[18]  M. B. Kasen.  The effect of grain boundaries on the recovery of electrical properties during annealing , 1970 .

[19]  S. A. J. Jahromi,et al.  Microstructure and mechanical properties relation in cold rolled Al 2024 alloy determined by X-ray line profile analysis , 2015 .

[20]  J. Lisoni,et al.  Ultrasound as a probe of dislocation density in aluminum , 2012, 1207.2658.

[21]  Ruslan Z. Valiev,et al.  A nanostructural design to produce high-strength Al alloys with enhanced electrical conductivity , 2014 .

[22]  Y. Kogure,et al.  Effect of Dislocations on Low-Temperature Thermal Conductivity and Specific Heat of Copper-Aluminum Alloy Crystals , 1975 .

[23]  F. Fickett.  Aluminum—1. A review of resistive mechanisms in aluminum , 1971 .

[24]  Sedat Karabay,et al.  Enhancement on Al–Mg–Si alloys against failure due to lightning arc occurred in energy transmission lines , 2013 .