共查询到20条相似文献,搜索用时 171 毫秒
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用高频等离子体阳极氧化技术,对铝膜紫外反射镜进行阳极氧化,得到紫外波段的反射率为66%和93%,它比单一的真空氧化铝膜的反射性能要好。在高频等离子体的阳极氧化中,尤以浮动氧化的反射性能更好(R=93%).铝膜的紫外反射率和俄歇电子谱表明,氧的暴露量控制100~200L之间,能在铝膜外表面生长一层22~35um的氧化铝保护膜,既能保持优异的反射特性,又有良好的抗腐蚀能力,是一种性能优越的紫外反射镜。 相似文献
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原子氧/紫外综合环境模拟实验与防护技术 总被引:1,自引:0,他引:1
北京卫星环境工程研究所研制的一台原子氧/紫外综合环境模拟设备。该设备采用了微波电子回旋共振和固体靶电荷交换中性化技术。可以产生通量密度为3×1015cm2.s,能量5 eV的中性原子氧束流。两盏30 W氘灯模拟太阳紫外光,波长范围为115 nm~400 nm。这台设备配备了样品光谱反射率原位测量系统。在这台设备上,进行温控白漆、TO/Kapton膜(聚酰亚胺镀氧化锡膜)、Ge/Kapton膜(聚酰亚胺镀锗膜)的原子氧环境、原子氧/紫外综合环境暴露试验。并进行了原子氧防护技术的研究,获得了初步的研究结果 相似文献
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在模拟空间环境原子氧暴露条件下,采用激光源原子氧对热控涂层材料Kapton薄膜、Kapton/Al薄膜二次表面镜进行了不同剂量的暴露试验。研究了这两种材料的质量损失、表面形貌随原子氧暴露剂量的变化关系,以及Kapton薄膜的光谱透过率、Kapton/Al薄膜二次表面镜的光谱反射率和太阳吸收比Δαs随原子氧暴露剂量的演化规律。结果表明:两种材料的质量损失随原子氧暴露剂量的增加呈线性增大;原子氧暴露后,试样表面呈"地毯"状形貌,且随暴露剂量的增加粗糙度变大;Kapton薄膜的光谱透过率、Kapton/Al薄膜二次表面镜的光谱反射率随原子氧暴露剂量的增加而降低,Kapton/Al薄膜二次表面镜的太阳吸收比Δαs随暴露剂量的增加而增大。最后对Kapton薄膜的存在寿命和Kapton/Al薄膜二次表面镜绝热平面的平衡温度进行了预测。 相似文献
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原子氧环境中聚酰亚胺的质量变化和侵蚀机制 总被引:1,自引:0,他引:1
用石英晶体微天平(QCM)原位监测并研究了聚酰亚胺薄膜在地面原子氧模拟装置中暴露时的质量变化.结果表明,聚酰亚胺薄膜在较低的原子氧束流通量暴露的初期,试样的质量先增加后降低,质量的降低与暴露的时间成正比.在高原子氧束流通量暴露的初期,试样质量的增加不明显,甚至一开始就发生稳态氧化失重.实验数据拟合的结果表明,原子氧对聚合物造成的侵蚀主要发生在有氧原子吸附的表面.质量的增加是由于较低的原子氧通量没有能完全氧化聚合物的表面.原子氧对聚合物材料的侵蚀机制服从Langmuir吸附理论. 相似文献
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Irina Gouzman Eitan Grossman Ronen Verker Nurit Atar Asaf Bolker Noam Eliaz 《Advanced materials (Deerfield Beach, Fla.)》2019,31(18)
The space environment raises many challenges for new materials development and ground characterization. These environmental hazards in space include solar radiation, energetic particles, vacuum, micrometeoroids and debris, and space plasma. In low Earth orbits, there is also a significant concentration of highly reactive atomic oxygen (AO). This Progress Report focuses on the development of space‐durable polyimide (PI)‐based materials and nanocomposites and their testing under simulated space environment. Commercial PIs suffer from AO‐induced erosion and surface electric charging. Modified PIs and PI‐based nanocomposites are developed and tested to resist degradation in space. The durability of PIs in AO is successfully increased by addition of polyhedral oligomeric silsesquioxane. Conductive materials are prepared based on composites of PI and either carbon nanotube (CNT) sheets or 3D‐graphene structures. 3D PI structures, which can expand PI space applications, made by either additive manufacturing (AM) or thermoforming, are presented. The selection of AM‐processable engineering polymers in general, and PIs in particular, is relatively limited. Here, innovative preliminary results of a PI‐based material processed by the PolyJet technology are presented. 相似文献
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聚合物材料表面原子氧防护技术的研究进展 总被引:1,自引:0,他引:1
聚合物材料具有质量轻、强度高等优点, 常被用作航天器表面的复合结构基材。原子氧是低地球轨道空间中成分含量最高的粒子之一, 对暴露在航天器表面的聚合物材料易形成大通量、高能量轰击, 造成其表面氧化侵蚀和质量损失, 使聚合物材料的性能发生不同程度的衰退, 也是导致航天器件可靠性降低、工作寿命缩短的主要环境因素。本文对当前国内外通用的几种聚合物材料表面原子氧防护技术进行了整理归纳, 其中表面化学改性方法结合了体材改性和常用防护涂层的优点, 得到的有机/无机复合改性防护层具有较好的综合防护性能。文中分析了近年来由计算模拟法开展原子氧与表面防护材料相关作用机理的研究, 指出采用计算模拟结合试验的研究方法, 有可能从本质上揭示复合改性层与原子氧的作用机理, 从而促进原子氧防护材料与防护技术的研究发展。 相似文献
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In this study, a series of polyimides had been prepared from bis-(4-aminophenoxyl) phenoxyl phosphine oxide (p-DAPO4) with corresponding dianhydrides via two-stage polycondensation method. The inherent viscosities of the polyamide acid were
in range of 0.43–0.92 dL/g, and atomic oxygen (AO) exposure experiment was conducted in a ground-based atomic oxygen effects
simulation facility with the filament charge and bound of magnetic field to determine the AO erosion-resistant properties
of the polyimide films. Field emission scanning electron microscopy (FE-SEM), attenuated total-reflection Fourier transform
infrared spectrometer and X-ray photoelectron spectrometer were employed to characterize the change on the surface of films
after AO exposure, and the mass loss of some phosphorus-containing polyimide films reduced to about 20% that of Kapton? HN film as AO fluence of 4.14 × 1020 atoms/cm2. The morphologies of heave residues of the polyimide films acting as a barrier to further erosion could be obtained from
FE-SEM. The results indicated that a phosphate-type layer was left on the surface of phosphorus-containing polyimide films
after AO exposure. 相似文献
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利用直流磁控溅射技术室温下在柔性聚酯薄膜衬底上制备了ITO薄膜,将ITO薄膜与有机玻璃和空白聚酯薄膜等介质材料组合成复合结构,最终得到吸波能力较强的透明吸波体.该吸波体在Ku带(12~18GHz)范围波段衰减低于-10dB,峰值超过-20dB,且在可见光区透光率达到68%. 相似文献
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(3-Glycidoxypropyl)-terminated silsesquioxane impact on nanomechanical properties of polyimide coatings exposed to atomic oxygen 总被引:1,自引:0,他引:1
Based on (3-glycidoxypropyl)silsesquioxane (GSSO) derived from the hydrolytic condensation of (3-glycidoxypropyl)trimethoxysilane (GPMS), GSSO-containing polyimide hybrid films were prepared using the sol-gel process and spin coating. Nanoindentation tests were carried out to study the influence of GPMS in the hybrid films on nanomechanical properties before and after exposure to atomic oxygen (AO) environments. The results show that hybrid films are three to four times harder than the usual plastic substrates. Compared with the unexposed AO samples, the elastic modulus (E) and the hardness (H) of the pristine Kapton AO-exposed samples significantly decreased, whereas the hardness of AO-exposed hybrid films increased slightly. This difference in nanomechanical properties is attributed to the chemical and the microstructural sample changes. 相似文献
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《Journal of Modern Optics》2013,60(10):1133-1139
The study of non-equilibrium charge carriers in semiconductor films by time-resolved reflectivity measurements is greatly simplified if the change in reflectivity change varies linearly with the photoinduced change in refractive index. In the present work it is shown that interference effects in the transparent layer influence this dependence significantly. The sample reflectivity can either increase or decrease, depending on the film thickness. If the reciprocal absorption coefficient of the semiconductor is smaller than the film thickness, a refractive index profile is created inside the layer. The reflection at this profile diminishes the influence of the beams reflected at the semiconductor-substrate interface. The changes in reflectivity then vary linearly with the changes in refractive index, independently of the film thickness. Numerical calculations were performed to help interpret time-resolved reflectivity measurements on amorphous silicon films. 相似文献