First-principles investigation of Cr-doped Fe2B: Structural, mechanical, electronic and magnetic properties

•Some physical properties of Cr-doped Fe2B have been predicted.•Overall, moduli firstly increase and then reduce with increasing Cr.•Hardness shows many fluctuations with increasing Cr.•All Cr-doped Fe2B have better ductility than Fe2B except Fe2Cr6B4 and Fe5Cr3B4.•The magnetic moments of the compounds do not monotonically reduce with increasing Cr.