Effect of Misch-metal content on microwave absorption property of Ce₂Co₁₇ alloy

The Ce_2−xMM_xCo₁₇ (x = 0.0, 0.3, 0.5, 0.8) powders were manufactured by vacuum melting and high-energy ball milling method so as to demonstrate the effect of Misch-metal (MM) (La-25.87 wt%, Ce-53.56 wt%, Pr-6.59 wt%, Nd-13.98 wt%) content on microwave absorption of Ce₂Co₁₇ alloy. The influences of MM content on the microstructure, saturation magnetization, electromagnetic parameters, and the microwave absorption performance of Ce₂Co₁₇ powders were investigated by the corresponding equipment. The results show that the particle size tends to increase, the reflectivity value of Ce_2−xMM_xCo₁₇(x = 0.0, 0.3, 0.5, 0.8) alloy increases first and then decreases and the minimum absorption peak frequency is shifted to the lower frequency band with the increase of MM content. Flaky Ce_1.7MM_0.3Co₁₇ demonstrated the best absorption performance where the RL_min reached − 40.17 dB at 8.72 GHz with an efficient bandwidth of 3.2 GHz (RL < − 10 dB, 7.44–10.64 GHz) at a given thickness of 1.8 mm. Adjusting the simulating thickness from 1.4 to 2.6 mm, the bandwidths range from 5.12 to 14.48 GHz. Furthermore, the Ce_1.2MM_0.8Co₁₇ alloy can achieve a reflectivity of  − 31.98 dB at 7.44 GHz and 1.8 mm, the effective bandwidth can also reach about 2.4 GHz, which still has better bandwidth performance, manifesting that proper MM content can optimize the microwave absorption property in C-band (4–8 GHz).