Fe2AlB2的高温氧化机制及吸波性能研究OA

Traditional wave-absorbing materials often exhibit performance limitations at high temperatures,which makes it difficult to meet performance demands in extreme high-temperature environments.Fe2AlB2 has garnered significant attention in the field of high-temperature wave absorption due to its nano-layered structure and exceptional high-temperature stability.This study synthesized Fe2AlB2 powder through a wet ball milling process followed by sintering in an argon atmosphere.Investigation was conducted to elucidate the oxidation mechanisms and to assess the evolution of its wave-absorbing properties at elevated temperatures.Additionally,electromagnetic simulation software was utilized to model the radar cross-section associated with its absorption process under 7 GHz microwave irradiation.The results indicate that the onset oxidation temperature of Fe2AlB2 is 671℃.As the oxidation temperature increases,a dense Al2O3 protective film forms on its surface,significantly enhancing its oxidation resistance.Beyond 1000℃,this Al2O3 film fractures,leading to transformation of the primary phases into Fe2O3,Al4B2O9 and amorphous B2O3.Within the oxidation temperature range of 300–800℃,the wave absorption performance of the sample progressively improves with increasing oxidation temperature,exhibiting particularly outstanding dielectric loss capabilities around 10 GHz.At an oxidation temperature of 900℃,the sample achieves a reflection loss of –42.60 dB at a frequency of 11.28 GHz,with corresponding a thickness of 2.8 mm.The Al2O3 film significantly enhances dielectric loss efficiency by inducing interfacial polarization loss at the"oxide film-matrix"interface.This study elucidates that oxidation mechanisms of Fe2AlB2 at varying temperatures and examines consequent impacts on wave-absorbing properties,thereby providing a theoretical foundation for its application in high-temperature wave-absorbing environments.