Effect of La Doping on the Microwave Absorption Performance of Dy2Co17 Alloys

Dy 2− x Co 17 La x ( x = 0.0, 0.1, 0.2, 0.3 and 0.4) alloy powders were prepared by vacuum smelting, homogeneous heat treatment and high-energy ball milling. The structure, morphology, magnetic properties and electromagnetic parameters of the powders were characterized by x-ray diffraction, scanning electron microscopy, vibration sample magnetometry and vector network analysis. On this basis, the microwave absorption properties of alloy powders were studied. With increasing amounts of La doping, the peak position of the reflection loss of the alloy moved to a low frequency, and the saturation magnetization decreased accordingly. When the doping amount was x = 0.4 and the matching thickness was 1.4 mm, the minimum reflection loss (RL min ) value was −27.4 dB at 8.56 GHz, and its effective absorption bandwidth (EAB) could reach 1.6 GHz (7.68–9.36 GHz). At the same time, the influence of the matching thickness on the value of reflection loss and peak frequency was also investigated.