基底结构对磁控溅射铜膜电磁屏蔽效能的影响

用直流磁控溅射法分别在涤纶机织布、针织布、纺粘非织造布表面制备铜薄膜,并用频谱分析仪与专用波导管测试所得样品在100 MHz~1.5 GHz之间的电磁屏蔽效能,用扫描电镜观察溅射样品的表面形貌,用显微镜观察基底布孔隙,并对结果进行比较分析。发现基底布表面结构形貌与孔隙对屏蔽效能均产生影响,前者更为显著。根据导电网络的连续性、几何结构的立体性及紧密程度、孔隙及未沉积的涤纶空白表面的几何结构对表面电阻、表面吸收损耗及反射损耗的影响,分析非织造布正反面屏蔽效能曲线的差异。非织造布正表面由于纤维粘连紧密,沉积铜后形成较连续的导电网络,屏蔽效能好;机织、针织布反之,屏蔽效能较差。除表面密实及平坦程度外,缝隙的尺寸及分布也影响屏蔽效能与频率曲线的形状。     

抗电磁辐射织物屏蔽效能的测试方法

电磁辐射对人体产生的危害主要表现为热效应、非热效应和累积效应，本文简介抗电磁辐射织物的种类以及电磁屏蔽的原理，着重论述屏蔽材料的屏蔽效能的测试方法(即：远场法、近场法、屏蔽室法)，并对抗电磁辐射织物的测试方法进行了探讨，结果表明屏蔽室法较能准确地评定抗电磁辐射织物的屏蔽效能。     

几种电磁屏蔽面料屏蔽效能的研究

选择铜镍涂层织物、银纤维交织织物、铜镍金属丝织物、不锈钢交织织物4种电磁屏蔽面料进行研究,利用同轴传输线法测试它们的电磁屏蔽效能。结果表明:材料中的金属丝比例越大,织物的电导率越大,电磁屏蔽效果越好。在金属丝含量相同的情况下,银丝的电磁屏蔽性能优于不锈钢。经洗涤后,银纤维交织织物和不锈钢交织织物的电磁屏蔽效果没有明显变化,而铜镍涂层织物和铜镍金属丝织物的电磁屏蔽性能均有明显衰减。     

电磁屏蔽织物屏蔽效能理论计算的研究进展

依据电磁屏蔽基本理论,总结了无孔金属板、有孔金属板和金属丝网格屏蔽体的屏蔽效能理论计算方法及公式。针对不同的织物类型或理论计算模型和方法,从有孔金属板、金属丝网格、拓扑结构模型及其他数值计算方面,综述了近年来关于电磁屏蔽织物屏蔽效能理论计算的研究进展。分析了现有电磁屏蔽织物屏蔽效能定量研究中存在的问题,指出应进一步研究纱线电磁参数及织物结构与屏蔽效能的理论关系。此外,指出在考虑纱线电磁参数和结构参数的基础上,建立织物屏蔽效能的解析公式用于指导工程计算为后续的研究方向。     

组织结构对针织物电磁屏蔽效能的影响

设计了几种代表性织物组织结构的不锈钢纤维混纺针织物,研究了织物组织结构对针织物电磁屏蔽效能的影响。织物组织结构选择充满系数较高的双罗纹组织、打鸡双面组织、添纱衬垫组织、衬纬组织和绕经组织,以降低织物厚度、密度、孔隙等因素对织物电磁屏蔽效能的影响。对所有织物进行了电磁屏蔽效能测试,结果显示:双罗纹织物、双面织物、添纱衬垫织物、衬纬织物的电磁屏蔽效能都很不理想,且远远低于含不锈钢纤维机织平纹布,但是绕经织物的电磁屏蔽效能要比其他组织的针织物的屏蔽效能高得多,基本能达到国标上对屏蔽服的屏蔽效能要求。绕经织物与其他几种针织物最大的不同就是在纵向多了一些连续的含不锈钢纤维的混纺纱。说明针织物组织结构是影响电磁屏蔽效能的关键因素,可通过在织物纵横向形成纵横交错的导通的金属网栅的方式来改善不锈钢纤维混纺针织物的屏蔽效能。     

电磁屏蔽织物的导电网格结构及其屏蔽效能的一般影响规律研究

分析了电磁屏蔽织物的纱线和织物的细微结构,提取了由具有加捻结构的金属纤维纱线构成的有效屏蔽网格结构,提出了对应的等效电路及通用影响参数。在1~18 GHz内,采用屏蔽室法,对裸铜丝、金属纤维纱线及织物样品的屏蔽效能进行了研究。结果表明:网格结构很好地反映了该类织物的有效屏蔽结构;金属纱线的周期间距是屏蔽效能的关键影响因素;金属纤维单向排列织物的屏蔽效能具有显著方向性;金属纤维纱线在交叉点处的导通概率对屏蔽效能的影响难以判断,尚需要进一步研究。研究结果对于电磁屏蔽织物具有普适性,为屏蔽效能定量数值计算提取了有效参数。     

Electromagnetic shielding effectiveness of carbon/stainless steel/polypropylene hybrid yarn-based knitted fabrics and their composites

In this study, a range of conductive hybrid knitted fabrics and their composites have been investigated for shielding effectiveness in the frequency ranges of 50 MHz to 1.5 GHz (low frequency) and 4 to 8 GHz (C-Band). Carbon and stainless steel (SS) filaments were combined in Dref-3 spinning machine and different hybrid yarns were prepared. The plain- and rib-knitted fabrics were made in V-bed flat knitting machine from the prepared hybrid yarns. The composite laminate was prepared by sandwiching a ply of fabric between the polypropylene films in compression moulding machine at 180 °C for 5 min under a consolidation pressure of 12 bar. All the fabrics and composites were tested for shielding effectiveness (SE) in coaxial transmission line and C-band waveguide with the help of vector network analyser. It was observed that fabric having both conductive loop and inlaid yarns exhibited higher SE of 20.2 dB than other fabrics in low-frequency range. However, in the composite form, carbon composite with SS inlaid yarn showed better SE of 45 dB than other composites. In C-band frequency range, conductive loop fabric structures yielded high shielding effect in course direction compared to wales direction. Compared to fabric form, the composite showed higher SE for all frequency ranges. This study proposes that knitted fabrics and their composites can be utilized as electromagnetic shields in wide frequency ranges.     

聚苯胺用于纯棉织物电磁防护功能整理的探讨

以盐酸为掺杂剂,过硫酸铵为氧化剂,在棉织物表面采用现场吸附聚合法生成一层导电聚苯胺,由此设计出一种具有良好电磁屏蔽效能的织物。对制备具有较高电导率聚苯胺织物的最佳工艺条件进行了分析。     

不锈钢金属纤维混纺织物的防微波辐射性能

文中就不同比例的不锈钢金属纤维 涤纶纤维混纺织物的微波屏蔽性进行了测试分析 ,探讨了影响混纺织物屏蔽效果的各种因素 ,为此类功能性产品的设计开发提供了参考。     

Production of electromagnetic shielding fabrics by optimization of electroless silver plating conditions for PET fabrics

This study aimed to investigate the optimal electroless silver plating conditions on poly (ethylene terephthalate) (PET) to develop electromagnetic shielding fabrics by comparison with two different activation agents (silver nitrate mixture and palladium chloride mixture). The add-on yield and thickness of plated fabrics were improved when the electroless silver plating was performed after the activation by silver nitrate mixtures compared to the activation by palladium chloride mixtures. The stability of plated surfaces after the activation by silver nitrate mixtures was proved after laundering by surface morphology and electromagnetic wave shielding effectiveness. The electroless silver plating condition was optimized to temperature of 15 °C, plating time of 30 min, dextrose concentration of 45 g/L, and silver nitrate concentrations as a plating material of 50 g/L. The electromagnetic wave shielding effectiveness and electrical conductivity of plated fabrics were maintained even after repeated laundering cycles. Electron probe microanalysis was concluded that the silver was attached on plated PET surfaces, and about 17.8% of silver was observed by inductive coupled plasma spectrometer.     

Electromagnetic shielding efficiency of nonwoven insulation panels designed with recycled textiles and copper wires

Insulation applications of nonwovens has become increasingly important in the construction and automotive industries since the late 1990s. Besides, recycling and reusing fibrous waste becomes one of the most important raw materials of nonwovens to promote effective use of resources recently. On the other hand, metals are now being increasingly replaced by thermoplastics for housing commercial equipment, due to flexibility, light weight, and low cost for electromagnetic shielding purposes. In this study, we design nonwoven insulation panels containing copper wires with different intensity and length to provide electromagnetic wave protection by using recycled textiles. The method is simple, the material is cheaper, and more importantly, the whole material can be produced by using only waste materials. The electromagnetic shielding characteristics of the panels were measured and discussed. The experimental results indicated that the variation in wire length and amount affects the electromagnetic (EM) shielding property. With this method, the products with electromagnetic shielding effect in certain areas can be developed. In particular, there is a big potential for electromagnetic shielding applications in wide bandwidth, such as 1125–2925 MHz.     

聚酯/聚苯胺复合织物化学镀铜效果的影响因素

利用超声波辅助化学镀方法在聚酯/聚苯胺复合织物表面均匀沉积金属铜.探讨聚苯胺的沉积条件、化学镀工艺中敏化和活化条件以及超声波辅助等条件对复合织物方阻值、增重率及结合性能等方面的影响.通过浸泡法和阳极极化法比较聚酯/聚苯胺、聚酯/铜和聚酯/聚苯胺/铜3种复合织物的耐腐蚀性能.利用扫描电镜对不同织物的表观形貌进行表征,同时...     

玻璃纤维/碳纤维织物基复合材料的电磁屏蔽性能

为增强碳纤维织物复合材料对电磁波的阻抗匹配性,减少二次反射,采用玻璃纤维调控碳纤维织物组织结构,并将其与水性聚氨酯复合,设计并制备了5种玻璃纤维/碳纤维(G/C)织物复合材料。借助超景深显微镜、矢量网络分析仪、模拟日光氙灯光源系统、红外热成像仪对G/C织物复合材料的形貌结构、电磁屏蔽性能、介电性能以及光热转化性能进行表征和分析。结果表明：在12.1 GHz下,纬纱采用2根玻璃纤维和单根碳纤维交替排列织造的G/C织物复合材料的屏蔽效能高达38.7 dB;G/C织物复合材料的组织结构变化可有效调控多种介电极化弛豫机制;G/C织物复合材料表面温度在模拟日光氙灯光源照射下响应速度快,其中玻璃纤维和碳纤维单根交替排列的G/C织物复合材料在2 kW/m²光照强度下照射300 s时,其表面温度可达71.8℃。     

双层及多层电磁屏蔽织物的屏蔽效能

为研究多层电磁屏蔽织物屏蔽效能情况,通过改变叠层角度、间距、叠层方式、层数,构建正交导电网格结构和单方向金属纱线平行结构的双层及多层电磁屏蔽织物,采用法兰同轴法测试其0.3~1.5 GHz内的屏蔽效能。结果表明,经纬向具有同样金属纱线间距时,织物屏蔽层厚度小于趋肤深度则双层织物的屏蔽效能明显高于单层织物,超过趋肤深度后增加不显著;3层及以上织物的屏蔽效能增加不明显;随层间距离增加,屏蔽效能呈增加趋势。仅纬向含金属纱线的双层织物,随双层织物中纬纱交叉角度的增加,逐渐形成金属纱线正交网格结构,屏蔽效能增大;双层织物中纬纱对齐叠放时,层间距离增加则屏蔽效能增大,纬纱垂直叠放时,层间距离增加则屏蔽效能降低。     

导电防辐射织物的研制

采用普通纤维混纺导电金属丝的方法,研制了几种导电防辐射织物.测定了织物的电磁波屏蔽性能和衰减量以及织物表面电阻.结果表明:采用镍金属丝和涤,棉纱的混纺织物防电磁辐射效果明显,金属丝含量越高,织物密度越大,防电磁辐射性能越好,织物在电磁辐射频率低于500 MHz时,屏蔽效能高于15dB;表面电阻为经向36Ω/2cm,纬向5Ω/2cm.     

涤纶基布磁控溅射铜膜及其电磁屏蔽性能

以不同组织结构的涤纶织物为基材,采用射频磁控溅射技术沉积纳米铜膜,研究织物结构对金属薄膜表面形貌、粗糙度和晶态结构的影响,并测试分析了表面磁控溅射纳米铜膜的涤纶织物电磁屏蔽性能。结果显示,非织造布、纳米纤维膜表面沉积的纳米铜膜颗粒平均粒径及其表面的粗糙度值较大,Cu(111)晶面上结晶度较高;在孔隙率较小且纤维紧密连接的非织造布表面沉积纳米铜膜,其纤维表面形成连续导电网络,表现出优良的屏蔽效果。     

Study on the conductive effectiveness of nanoscale copper films sputtered on the surface of polyester nonwoven fabrics

Nanoscale copper (Cu) thin films were deposited onto the surface of nonwoven polyester fabrics by RF (radio frequency) magnetron sputtering technique at room temperature. In order to evaluate conductive effectiveness of nanoscale copper films, the samples were placed at room temperature in the atmospheric conditions for 60 and 90 days, respectively. The surface morphology changes of nanoscale copper (Cu) film were characterized by field emission scanning electron microscope (FE-SEM), and then X-ray photoelectron spectroscopy (XPS) was used to characterize the surface physical and chemical structure changes of samples placed for 60 and 90 days. The resistance change of samples was measured in detail to evaluate conductive properties of samples. The experimental results showed that the surface of copper films was broken and the continuity was destroyed after 60 days, while exposed in the normal atmospheric environment for 90 days, the cracks gradually expanded, there is no change in the atomic species on the surface of samples placed before and after. The valence of oxygen atom did not change, copper flims on the surface of samples is elemental and not be oxidized to cupric oxide or other materials. With the increase in standing time, the resistance of samples placed for 60 days was gradually increased and therefore the conductivity was decreased, while resistance remained unchanged and conductive performance was stable when the samples were placed after 60 days.     

Development and characterisation of polyaniline/polyamide (PANI/PA) fabrics for electromagnetic shielding

In this study, novel conductive fabrics were developed by polymerising of aniline onto the polyamide (PA)-knitted fabrics. The fabric treatment was done by the chemical polymerisation method at 0.5, 0.8 and 1.2?M aniline concentrations. Hydrochloric acid as acidic medium and ammonium per sulphate as oxidant were employed during the polymerisation process. The polyaniline (PANI)-treated PA fabric structures were fully characterised and evaluated in terms of their electromagnetic shielding effectiveness, absorption and reflection characteristics and tensile properties. Additionally, the fabrics were examined by scanning electron microscope (SEM) for the surface morphology and Fourier transform infrared spectroscopy for the chemical functionality. The electromagnetic shielding effectiveness, absorption and reflection characteristics were determined by Network Analyzer with a frequency ranged from 15 to 3000 MHz. The electrical characteristics were measured by the two ends method. It has been concluded that the bursting strength values of the treated fabrics reduced when the amount of monomer in the concentrations decreased as compared to the untreated fabrics. It is interesting to note that 1.2 M treated fabric had the highest bursting strength values as compared to the other treated fabrics. It was also found that 0.5 M concentration of PANI-treated fabric had the lowest surface resistivity due to this it showed the highest conductivity value. Another important finding is that the 0.5 M-aniline treated fabric had the highest shielding effectiveness.     

抗电磁辐射精纺毛织面料的开发及其影响因素

 本文旨在通过两种加工方式研制成抗电磁辐射精纺面料,一种是镀银长丝与羊毛单纱并捻合股织造成并捻织物,一种是镀银长丝直接用作经纬纱与羊毛交织成交织物。由织物的屏蔽效能测试结果可知,并捻织物电磁屏蔽效能在2250-2650MHz波段内优于交织物,最高可达85dB,具有较好的抗电磁辐射效果。另外,经纬密度的变化对织物电磁屏蔽能力也有一定影响,两种织物紧度在78%左右、交织物羊毛与长丝比例为1:2时电磁屏蔽效果较好。其结果对开发高性能抗电磁辐射精纺面料有一定的指导意义。     

化学镀银涤纶织物的制备及其性能

利用化学镀方法制备镀银电磁屏蔽涤纶织物.分别采用场发射电镜( FE-SEM)、电子能谱(EDS)和X射线衍射(XRD)表征镀层的表面形貌、成分和结晶情况;考察了织物的厚度、增重率、耐摩擦色牢度、表面电阻、抗静电性、拉伸断裂强力、断裂伸长率、刚柔性、悬垂性以及透气性.结果表明:镀层为高纯度立方面心结构的单质银;化学镀银后...