Enhanced Magnetic Properties of Spark Plasma Sintered (La/Ce)–Fe–B Magnets

La substitution for Ce inhibits the growth of the CeFe
₂
phase and promotes the formation of the single 2:14:1 phase, leading to an improvement in the magnetic properties of melt-spun (La/Ce)
₃
Fe
₁₄
B ribbons. Among which, the (La
_0.3
Ce
_0.7
)
₃
Fe
₁₄
B ribbon produced a high remanence of 6.86 kG, a coercivity of 5.51 kOe, and a maximum energy product (BH)max of 7.68 MGOe. After spark plasma sintering, the compacted (La
_0.3
Ce
_0.7
)
₃
Fe
₁₄
B magnet with good remanence and coercivity was successfully prepared, and these properties were enhanced to 5.14 kG and 5.60 kOe, respectively, leading to an energy product of 4.59 MGOe for the magnet with 5 wt % NdCu addition.