Template-assisted electroplating of Sm-Co composite nanowires: Issue of boric acid additive via R-D process

•Electroplating of the Sm-Co nanowires was conducted using linear sweep voltammetry.•Growth mechanisms of the Sm-Co nanowires with a core–shell structure inside AAO pores explained.•To obtain neatly isolated Sm-Co nanowires, the AAO templates were etching using CH3OH based NaOH solution.•The R-D process was performed annealing using the mixture of NaCl, KCl, and Ca granules.•Boric acid prevented transformation into the Sm2Co17 phase during the R-D process.