红外雷达复合隐身技术探讨

简要介绍了目前红外、雷达隐身技术的现状和存在的问题,并对国外目前研究的掺杂氧化物半导体材料、导电聚合物、视黄基席大碱盐、涂覆金属空心导电微珠和纳米吸波材料等新型红外雷达兼容隐身材料进行了详细探讨,最后沦述了红外雷达复合隐身涂层技术的隐身机理和发展现状.     

影响低发射率涂层与超材料吸波体兼容的关键因素探究

为了实现8~14μm波段低反射率涂层与超材料吸波体的兼容隐身,探究了影响低发射率涂层与超材料兼容性能的关键因素。采用IR-2型发射率测试仪测定涂层在8~14μm波段的发射率,用弓形法测量了超材料涂覆涂层前后的反射损耗曲线,并采用矢量网络分析仪测试了涂层电磁参数。结果表明,涂覆低发射率涂层后,可将超材料吸波体的红外发射率降至0.126,但是其对超材料吸波体原有吸波特性影响较大,平均反射损耗以及吸收带宽都有所减小。在涂层4个电磁参数中,介电常数实部为影响低发射率涂层与超材料兼容的关键因素,低发射率涂层的介电常数实部较高,导致本征阻抗较小,与自由空间的阻抗不匹配,对雷达波的反射较多,涂覆后对超材料吸波体原有反射损耗特性影响大。     

聚氨酯涂料红外发射率性能研究

文中主要通过对聚氨酯作为成膜物质时其红外性能和物理化学性能研究,通过加入纳米改性填料和改变涂装工艺的方法来降低其红外发射率,同时涂膜具有优良的物理化学性能.通过研究,用聚氨酯作为成膜物质,纳米NiO包覆片状铝粉和SiO2粉等为填料,得到了浅绿色涂层的红外发射率仅为0.39,具有一定的红外隐身与可见光隐身、雷达隐身相兼容效果,同时发现涂层的电导率、磁导率对涂层的红外发射率的影响也很大.     

涂覆吸波材料目标RCS测量校准试验研究

雷达吸波涂层易受涂覆工艺、物理特性和气动应力等因素影响而破坏飞机整体的隐身特性。为评估雷达吸波涂层状态,在紧缩场对涂覆雷达吸波材料的目标展开RCS测量和分析。雷达散射测量系统的测量精度受定标体几何参数精度、测量方法、校准方法、系统稳定性等多种因素影响。在金属球定标体几何参数、场地制造装配精度和安装定位精度等已溯源至国家基准的基础上,针对测量和校准需求,研究了替代置换法的测量校准原理,开展了测量和校准试验,结果表明:在扫频测量基础上,通过时域频域变换、背景矢量对消、时间窗等技术滤除杂波干扰而获取线性度较好的系统校准曲线,用于涂覆雷达吸波材料目标的RCS测量校准,能有效提高测量效率和精度,确保量值一致,满足隐身飞机雷达隐身状态监控和校准需求。     

红外与雷达复合隐身研究

本文从材料的角度分析了红外隐身和雷达隐身各自需要的条件,指出在采用分层涂覆法时,红外与雷达复合隐身的技术关键是在满足红外隐身层目标低发射率的同时,能让雷达波顺利穿透该层,使雷达波进入雷达隐身层而被有效耗散.最后介绍了用掺杂半导体材料和纳米材料实现红外与雷达复合隐身的可能性.     

等离子体复合雷达吸波材料的电磁特性

随着现代先进探测技术的不断发展,对隐身技术的要求不断提高.传统的雷达吸波材料隐身技术在6 GHz以上微波频段内有较好的隐身效果,而等离子体隐身技术在低频（6 GHz以下）更易于实现.基于此,文中采用雷达吸波材料和等离子体技术复合,利用同轴网格辉光放电产生等离子体与雷达吸波材料相结合,并进行了隐身性能测试.测试结果表明,复合隐身效果优于单一隐身技术的隐身效果,且通过调节等离子体的放电功率等参数,易于实现隐身效果的控制.本文的研究工作可以为等离子体和雷达吸波材料复合隐身技术相关研究提供一定参考.     

红外隐身涂层光谱发射率测量定标研究

受涂覆工艺、物理特性和气动应力等因素影响,飞机红外隐身涂层容易产生裂纹、剥落等损伤.监控涂层光谱发射率是红外隐身涂层状态监控的一种有效手段.光谱发射率监控设备的定标直接影响涂层光谱发射率测量结果的可信度,进而影响飞机红外隐身特性的评估结果.针对光谱发射率测量定标需求,研究了积分球定向积分反射比测量系统定标方法,并开展红...     

不同吸波涂层对三维复杂目标的RCS影响的分析

利用有限元-快速多极子算法(FEM-FMM)分析了三维复杂目标涂有不同吸波涂层的雷达散射截面(RCS).以圆锥体为例,详细计算分析了涂敷有耗各向同性、正单轴各向异性、负单轴各向异性和纳米吸波材料4种典型吸波材料对目标电磁散射特性的影响,并首次讨论了每种吸波材料随不同涂层厚度对RCS的影响,得到了最佳隐身效果的吸波材料和涂层厚度的组合.结果表明,涂敷最佳吸波材料目标的后向RCS比目标没有吸波涂层时可以降低16.6dB.     

8~14μm波段水性红外隐身涂料研究

从基体树脂、填料和涂层综合性能三方面对8~14m波段水性红外隐身涂料进行了研究。用红外发射率测量仪测量了涂层在8~14m波段的红外发射率,用红外光谱仪测量了树脂红外吸收图谱,用扫描电镜观察了涂层表面形貌。结果表明,丙烯酸树脂在8~14m波段有较高的红外透明性,适合做涂料基体树脂;铝银浆能在涂层中形成致密的反射层,适合做红外隐身涂料的填料;填料的粒径、含量和形态都对涂层的发射率有较大的影响;选用钢板为基材,以丙烯酸树脂为基体树脂,粒径2000目、浮铝百分比为50%的铝银浆为填料,当涂层中填料含量为15%时,测得其发射率为0.34。     

聚异戊二烯/丙烯腈基织物涂层在8～14Um波段的红外低发射率

以异戊二烯、丙烯腈为单体乳液聚合制备了聚异戊二烯/丙烯腈水性黏合剂.用该黏合剂和金属填料制备了一种红外隐身水性涂料,涂刷于织物载体上,制得了织物红外隐身涂层.研究了黏合剂、金属填料及载体对涂层在8～14 μm红外发射率的影响.用红外光谱仪表征了黏合剂的红外吸收,红外发射率测量仪表征了材料在8～ 14μm的红外发射率,热...     

Electrosprayed Enzyme Coatings as Bioinspired Alternatives to Bioceramic Coatings for Orthopedic and Oral Implants

The biological performance of orthopedic and oral implants can be significantly improved by functionalizing the non‐physiological metallic implant surface through the application of biologically active coatings. In this paper, a cost‐effective alternative to traditional biomedical coatings for bone substitution through exploitation of the specific advantages of the electrospray deposition technique for the immobilization of the enzyme alkaline phosphatase (ALP) onto the implant surface is presented. Since ALP increases the local inorganic phosphate concentration required for physiological mineralization of hard tissues, ALP coatings will enable enzyme‐mediated mineralization onto titanium surfaces. To evaluate the bone‐bioactive capacity of the ALP‐coated titanium surface, soaking experiments are performed. Although the purely inorganic so‐called simulated body fluid is the standard in vitro procedure for predictive studies on potential bone bonding in vivo, an alternative testing solution is proposed that also contains organic phosphates (cell culture medium supplemented with the organic β‐b;‐glycerophosphate (β‐b;‐GP) and serum proteins), thereby resembling the in vivo conditions more closely. Under these physiological conditions, the electrosprayed ALP coatings accelerated mineralization onto the titanium surface as compared to noncoated implant material by means of enzymatic pathways. Therefore, this novel approach toward implant fixation holds significant promise.     

Optical Properties of Window Coatings

Window coating used for the building in recent years is described.Important design principles, practical coating materials, and attainable optical properties for research-type coatings are introduced.Discussion is carried out on the spectrally selective coatings, the electrochromic coatings, and the thermochromic coatings.     

用于元件保护的保形涂覆技术

印刷电路板组件(Printed circuit board assemblies,PCBA)常常要经受极端气候环境条件和机械应力的考验.在电子产品组装过程中可能出现的环境变化负载包括高或低空气湿度、高或低温、低气压、迅速的天气变化、水汽凝聚、微生物影响和玷污等.所以,在保证PCBA的工作正常方面,防护和绝缘变得越来越重要,特别是要满足严格的质量和服务寿命要求的情况下.     

Particulate Coatings with Optimized Haze Properties

The haze factor, which describes the fraction of light that is scattered when passing through a transparent material, is of general importance for any optical device, from milk glass shielding visibility while providing ambient lighting to solar cells that are optimized by sophisticated light management layers. Often, such active layers are fabricated from particulate materials that are deposited as thin films on a substrate. Here, the effect of structural arrangement, position, and orientation of particles on the resulting haze factor is investigated. A mathematical optimization model that iteratively alters the particle layer structure to maximize or minimize the haze factor for a range of optimization scenarios is designed. Colloidal self‐assembly techniques are then used to replicate typical particle structures found in the optimized designs and correlate the macroscopically measured haze values to the predictions of the optimization. The results indicate general design rules that control the haze value in particle layers. Non close‐packed structures with distributed scatterers and high degrees of order provide minimal haze values while chain‐like arrangements and small clusters maximize the haze of a particle layer. Finally, the findings are transferred to metal nanohole films as model transparent electrodes with controlled haze values.     

二极管泵浦Nd：YVO4倍频激光器使用的光学薄膜

讲座了二极管泵浦Nd:YVO4倍频激光器中使用的一系列光学薄膜,膜系类型涉及截止滤光片、增透膜等。根据设计对称匹配膜层的分析,利用计算机膜系设计优化软件对膜系进行优化,得到损耗小,利用于制备、重复性好的膜系设计。用于实际制备,取得较好的效果。     

等离子体增强化学气相沉积端面减反膜的研究

利用等离子体增强化学气相沉积(PECVD)技术制作半导体有源器件端面减反膜的方法简单易行,且适合进行大规模在片制作.采用1/4波长匹配法对减反膜的折射率、膜厚及其容差进行了理论设计,并在选定折射率下,对PECVD的沉积速率进行了测量.在此基础上,制作了1.31 μm InGaAsP氧化膜条形结构超辐射发光二极管,通过测定输出光谱调制系数的方法确定出减反射膜的反射率为6.8×10-4,并且具有很好的可重复性.     

Copper‐Free Clickable Coatings

The copper‐catalyzed azide–alkyne 1,3‐dipolar cycloaddition (CuAAC) is extensively used for the functionalization of well‐defined polymeric materials. However, the necessity for copper, which is inherently toxic, limits the potential applications of these materials in the area of biology and biomedicine. Therefore, the first entirely copper‐free procedure for the synthesis of clickable coatings for the immobilization of functional molecules is reported. In the first step, azide‐functional coatings are prepared by thermal crosslinking of side‐chain azide‐functional polymers and dialkyne linkers. In a second step, three copper‐free click reactions (i.e., the Staudinger ligation, the dibenzocyclooctyne‐based strain‐promoted azide–alkyne [3+2] cycloaddition, and the methyl‐oxanorbornadiene‐based tandem cycloaddition?retro‐Diels?Alder (crDA) reaction) are used to functionalize the azide‐containing surfaces with fluorescent probes, allowing qualitative comparison with the traditional CuAAC.     

重复率激光对光学薄膜的破坏

实验研究了在不同波长、不同脉宽激光作用下，光学薄膜破坏的重复率效应并结合理论分析和在破坏过程中的光热监测，探讨了光学薄膜累积破坏的机理。     

深紫外波段光学薄膜研究进展

随着准分子激光、自由电子激光以及全固态深紫外激光等深紫外激光光源的推广应用,近年来,深紫外波段光学薄膜技术得到了快速的发展.综述了深紫外波段增强型铝镜、氧化物薄膜、氟化物薄膜以及氧化物和氟化物的混合薄膜的最新研究进展.     

Nanostructured ITO/SiO2 Coatings

Semiconductors - The influence of a SiO2 layer deposited onto nanostructured transparent conductive films of indium and tin oxide (ITO) on their optical characteristics is investigated. For this...