The electromagnetic (EM) wave absorbing properties of Cr₂AlB₂ powders and those after high‐temperature oxidation were investigated. Coupling of magnetic and dielectric loss enables Cr₂AlB₂ with good absorption properties. The minimum reflection loss (RL) value is −44.9 dB at 8.5 GHz with a thickness of 2.7 mm, and the optimized effective absorption bandwidth (E_AB) is 4.4 GHz (13.0‐17.4 GHz) with a thickness of 1.6 mm. After oxidation at 750, 900, and 1000°C for 2 h, the minimum RL values, respectively, are −23.9 dB (17.5 GHz, 1.5 mm), −41.4 dB (16.5 GHz, 1.5 mm), and −39.5 dB (8.0 GHz, 3.0 mm); and the corresponding E_AB values, respectively, are 3.8 GHz (13.6‐17.4 GHz, 1.7 mm), 4.1 GHz (13.5‐17.6 GHz, 1.6 mm), and 4.4 GHz (13.0‐17.4 GHz, 1.7 mm). With an absorber thickness of 1.5‐4.0 mm, the E_AB with a RL value of less than −10 dB can be tuned in a broad‐frequency range 5.0‐18.0 GHz, which basically covers C (4‐8 GHz), X (8‐12 GHz), and Ku (12‐18 GHz) bands. These results demonstrate that Cr₂AlB₂, as a high‐efficient and oxidation‐resistant absorber, is a promising candidate for microwave absorption applications and can retain good EM wave absorbing properties after high‐temperature oxidation.

中文翻译：

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Cr2AlB2粉末的电磁波吸收特性及高温氧化的影响

研究了Cr ₂ AlB ₂粉末和高温氧化后的电磁波吸收特性。磁损耗和介电损耗的耦合使Cr ₂ AlB ₂具有良好的吸收性能。最小反射损耗（RL）值在8.5 GHz时为2.7 mm厚度为−44.9 dB，最佳有效吸收带宽（E _AB）在4.4 mm（13.0-17.4 GHz）时为1.6 mm厚度。在750、900和1000°C氧化2小时后，最小RL值分别为-23.9 dB（17.5 GHz，1.5 mm），-41.4 dB（16.5 GHz，1.5 mm）和-39.5 dB（ 8.0 GHz，3.0毫米）；和相应的ë _AB分别为3.8 GHz（13.6-17.4 GHz，1.7 mm），4.1 GHz（13.5-17.6 GHz，1.6 mm）和4.4 GHz（13.0-17.4 GHz，1.7 mm）。吸收体厚度为1.5-4.0 mm时，RL值小于-10 dB的E _AB可以在5.0-18.0 GHz的宽频率范围内进行调谐，基本上覆盖了C（4-8 GHz），X（ 8-12 GHz）和Ku（12-18 GHz）频段。这些结果表明，Cr ₂ AlB ₂作为一种高效且抗氧化的吸收剂，是微波吸收应用中的有前途的候选物，并且在高温氧化后可以保持良好的EM波吸收特性。