Intrinsic properties, phase constitution and microstructure of novel RE-Fe-B strip-casting alloys based on misch metal

•Pr-Nd-MM-Fe-B alloy strips with different MM were prepared by strip-casting.•The phase constitution, microstructure and magnetic properties were studied.•When x ≥ 0.50, REFe2 phase exists inevitably and increases gradually.•When x ≥ 0. 50, La and Ce aggregate in the RE-rich phase clusters.•The content of Fe rises with the increase of MM in RE-rich phase.•The interfaces between of RE2 Fe14 B phase and RE-rich phase is indistinct.•The lattice parameters and magnetic properties with 35 wt.% MM is abnormal.•When x = 0.35, the Ce valence shifting toward +3 with one 4f moment.