Microwave absorption properties and multilayer absorber design of La2FexCo14-xB with easy cone anisotropy

The effective integration of microwave attenuation capability with impedance matching is crucial for designing and optimizing microwave-absorbing materials. In this study, we investigate the microwave absorption properties of La ₂Fe _xCo _14-xB with easy cone anisotropy. By adjusting the filling rate of La ₂Fe ₄Co ₁₀B, we have successfully enhanced the microwave attenuation capability of the composite and optimized its impedance matching. At a filling rate of 25 vol%, La ₂Fe ₄Co ₁₀B exhibits an effective absorption bandwidth (EAB) of up to 7.5 GHz at a thickness of 1.5 mm, superior to most single-layer absorbing materials. Furthermore, we introduce a novel concentration-dependent layered structure comprising La ₂Fe ₄Co ₁₀B/paraffin composites at designated filling rates of 10 vol%, 25 vol%, and 40 vol%, respectively. This 3-layer absorber exhibits outstanding microwave absorption performance. With a total thickness of 2.9 mm, the 3-layer absorber achieves a strong absorption peak of −55.1 dB at 11.0 GHz, while also possessing an EAB of 9.8 GHz. Based on Maxwell`s equations, which encompass normalized input impedance and loss analysis, it is demonstrated how the 3-layer structure efficiently utilizes the dielectric and magnetic loss properties of La ₂Fe ₄Co ₁₀B to achieve robust absorption across an ultra-wide frequency band. This study not only offers a fresh perspective on the microwave attenuation capabilities of materials but also introduces novel strategies for the design of advanced materials aimed at high-performance microwave absorption.