Effect of ferromagnetic Fe96.5Si3.5 dopant on microstructure and magnetic properties of hot-deformed Nd-Fe-B magnets

•The remanence and the maximum magnetic energy product are significantly improved by the addition of FeSi.•The multi-layer structure is formed near the FeSi phase region by the addition of FeSi.•The effects of FeSi addition on the magnetization behaviors were investigated by magneto-optical Kerr microscope.•The overall texture is improved and the region of the non-oriented coarse grains is reduced by the addition of FeSi.