Abstract:

C/UV curable resin electromagnetic metamaterials were prepared by 3D printing, and the effects of heat treatment temperatures (700℃, 800℃ and 900℃) of C-balls on the microwave absorption properties of the prepared C/UV curable resin samples were investigated. The results showed that the microwave absorption properties of C/UV curable resin electromagnetic metamaterials indicated a trend of first enhancement and then decrease with increasing heat treatment temperature. The best performance of C/UV curable resin samples was obtained when the heat treatment temperature was 800℃. Its minimum reflection loss of -42.9dB was obtained at 8.6mm matched thickness, and the effective absorption bandwidth at 9.4mm matched thickness was up to 6.0GHz. The performance differences of different samples were related to their impedance matching and attenuation coefficients, and the graphitization degree of the C-balls was lower at 700℃ heat treatment temperature, and the reflection of electromagnetic waves was lower at 9.4mm matched thickness. At 700℃, the graphitization degree of C-balls was low, which resulted in a weak reflection of electromagnetic waves, while the low graphitization also led to a small attenuation coefficient and poor microwave absorption performance of this sample. When the heat treatment temperature rose to 800℃, the enhanced graphitization of the C-balls improved the high-frequency polarization relaxation and attenuation coefficients so that the sample exhibited excellent microwave absorption properties. With the increase of heat treatment temperature to 900℃, the graphitization degree of C-balls was further increased, leading to the high-frequency polarization of the sample. As the heat treatment temperature increases to 900℃, the graphitization degree of the C-balls was further enhanced, resulting in the suppression of the high-frequency polarization relaxation of the sample and the weakening of the impedance matching, and thus the microwave absorption intensity and effective absorption bandwidth of the sample began to weaken. The above study clarified the influence of heat treatment temperature on the microwave absorption performance of carbon materials, which provided an effective reference for the study of this type of materials, and the preparation method of 3D printing adopted in the study also provided a new idea for the exploration of the preparation process of new microwave absorption materials.

Key words: C/ultraviolet curing (C/UV) curable resin, hydrothermal, 3D printing, microwave absorption, electronic materials

摘要：

通过3D打印制备了碳/紫外光固化（C/UV）树脂电磁超材料，研究了C球的热处理温度（700℃、800℃和900℃）对C/UV树脂电磁超材料微波吸收性能的影响。结果表明，随着热处理温度的上升，所制备的C/UV树脂样品的微波吸收性能呈现出先增强后下降的趋势。当热处理温度为800℃时，C/UV树脂样品的性能最佳，其在8.6mm匹配厚度下获得了-42.9dB的最小反射损耗，在9.4mm匹配厚度的有效吸收带宽可达6.0GHz。不同样品的性能差异与其阻抗匹配和衰减系数有关，在700℃的热处理温度下，C球的石墨化程度较低，对电磁波的反射较弱，同时低石墨化程度也导致该样品衰减系数较小，微波吸收性能较差；当热处理温度上升至800℃时，C球的石墨化程度提升，提高了高频极化弛豫和衰减系数，使该样品表现出优异的微波吸收性能；随着热处理温度上升至900℃，C球石墨化程度进一步提升，导致样品高频极化弛豫受到抑制，阻抗匹配也减弱，故该样品的微波吸收强度和有效吸收带宽开始减弱。以上研究明确了碳材料热处理温度对其微波吸收性能的影响规律，为该类材料的研究提供了有效参考，同时研究所采用的3D打印制备方法也为新型微波吸收材料制备工艺的探索提供了新思路。

关键词: 碳/紫外光固化树脂, 水热, 3D打印, 微波吸收, 电子材料