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Microstructure and electrical conductivity of aluminium/steel bimetallic rods processed by severe plastic deformation


Equal-channel angular pressing (ECAP) was used to fabricate Al/steel bimetallic rod for potential application in overhead transmission conductors. Bimetallic rods consisted of an austenitic stainless steel 316L core and an Al alloy 6201 cladding layer. By means of ECAP processing at 175°C, increase of mechanical strength without loss of electrical conductivity was achieved for one particular rod geometry out of three geometries tested. X-ray diffraction and transmission electron microscopy were employed to analyse how the microstructure was influenced by the number of processing passes and the bimetallic rod geometry. The co-deformation mechanism of the bimetallic rod under ECAP and accelerated dynamic ageing of Al alloy 6201 were discussed based on the microstructure characterisation results.

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The authors appreciate the excellent technical assistance provided by Monash Centre of Electron Microscopy (MCEM). YQ is grateful to Dr. Enrico Bruder for technical discussions and Dr. Annalena Wolff for FIB training. YE acknowledges funding support from the Russian Ministry for Education and Science (Grant #14.A12.31.0001). RL acknowledges funding support from Australian Research Council (Grant # LP0991316).

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Correspondence to Yuanshen Qi or Yuri Estrin.

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Qi, Y., Lapovok, R. & Estrin, Y. Microstructure and electrical conductivity of aluminium/steel bimetallic rods processed by severe plastic deformation. J Mater Sci 51, 6860–6875 (2016).

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  • Severe Plastic Deformation
  • Friction Stir Processing
  • Accumulative Roll Bonding
  • Extrusion Direction
  • Steel Core