Exchange-coupled hard–soft magnets have been considered as promising microwave absorbers. However, it is difficult to make further breakthrough in microwave absorption performance due to the deficient dielectric loss. In this work, Cu/Fe₃O₄/BaZr_0.6Ni_0.6Fe_10.8O₁₉ composites with sufficient magnetic exchange coupling interaction and impressive dielectric loss were successfully fabricated. The results show that the crystallinity of Fe₃O₄ enhances gradually by increasing the secondary heat treatment temperature. More spherical Fe₃O₄ particles attach to the surfaces of flake-like BaZr_0.6Ni_0.6Fe_10.8O₁₉ particles from room temperature to 400 °C, increasing the hard/soft magnetic interfaces, while self-aggregation of Fe₃O₄ becomes more pronounced and Cu is oxidized violently to CuO with the further increase of temperature to 600 °C. Eventually, the sample heated at 400 °C shows the strongest attenuation ability due to the common enhancement of magnetic and dielectric loss, and hence exhibits the optimum microwave absorbing performance with a broad absorbing bandwidth of 5.28 GHz at a thin thickness of 2.0 mm.

中文翻译：

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充分的磁交换耦合相互作用和令人印象深刻的介电损耗所产生的高效微波吸收性能

交换耦合的软软磁铁被认为是有前途的微波吸收器。但是，由于介电损耗不足，因此难以进一步突破微波吸收性能。在这项工作中，成功地制备了具有足够的磁交换耦合作用和令人印象深刻的介电损耗的Cu / Fe ₃ O ₄ / BaZr _0.6 Ni _0.6 Fe _10.8 O ₁₉复合材料。结果表明，通过提高二次热处理温度，Fe ₃ O ₄的结晶度逐渐提高。更多球形Fe ₃ O ₄颗粒附着在片状BaZr表面从室温到400°C， _0.6 Ni _0.6 Fe _10.8 O ₁₉颗粒增加了硬/软磁界面，而随着温度的进一步升高，Fe ₃ O _4的自聚集变得更加明显，并且Cu被剧烈氧化为CuO。 600℃。最终，加热到400°C的样品由于磁和介电损耗的共同增强而显示出最强的衰减能力，因此在厚度为2.0 mm的情况下，具有5.28 GHz的宽吸收带宽，具有最佳的微波吸收性能。