1 Copper-Aluminium Hybrids for Energy Applications R. Lapovok 1, 2 , V.V. Popov Jr. 3 , Y. Qi 1 , A. Kosinova 1 , A. Berner 1 , C. Xu 1, 4 , E. Rabkin 1 , R. Kulagin 5 , J. Ivanisenko 5 , B. Baretzky 5 O.V. Prokof'eva 6 , A.N. Sapronov 6 , D.V. Prilepo 6 , Y. Beygelzimer 7 1 Department of Materials Science and Engineering, Technion – Israel Institute of Technology, Haifa 3200003, Israel 2 Institute for Frontier Materials, Deakin University, Waurn Ponds, Vic 3216, Australia 3 Israel Institute of Metals, Technion Research & Development Foundation Ltd., Israel 4 School of Materials Science and Engineering, Xi'an University of Technology, Shaanxi 710048, China 5 Institute of Nanotechnology, Karlsruhe Institute of Technology, Eggenstein- Leopoldshafen 76344, Germany 6 Donetsk Institute for Physics and Engineering named after A.A. Galkin, 83114, Donetsk, Ukraine 7 Donetsk Institute for Physics and Engineering named after A.A. Galkin, National Academy of Sciences of Ukraine, 03028, Kyiv, Ukraine Abstract This study is inspired by the potential of application-designed aluminium-copper conductors. This work combines recently discovered advantages of hybrids with one constituent having a helical architecture with the benefits provided by severe plastic deformation (SPD) methods. The hybrids are made by embedding copper helixes in melted aluminium and subjecting cast hybrid ingots to different SPD techniques. The electrical conductivity, microstructure features and strength of the produced samples are discussed in relation to effect of SPD and annealing on both constituents and an interface zone formed during the hybrids’ production. A model describing the effective electrical conductivity of hybrid samples, consisting of an aluminium matrix with an embedded copper helix and intermetallic containing interface, is developed and justified by experimental data. The model is shown to be instrumental for analysis of the effect of the helix’s parameters and interface width on effective conductivity of the hybrid samples and could be used for optimal design of hybrid conductors. Keywords: Copper-aluminium hybrid materials, conductivity, interface, intermetallic, microstructure