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。

Research on conductive grid structure and general influence factors to shielding effectiveness of electromagnetic shielding fabrics

The fine structure of yarns and fabrics in the electromagnetic shielding fabrics are analyzed. The effective shielding grid structure made of twisted metal fiber yarns is extracted. The corresponding equivalent circuit and general factors are put forward. The SE in 1~18GHz of three kinds of samples made of bare copper and metal fiber yarns and fabrics are researched using shielded chamber method. It shows that grid structure reflects the effective shielding structure of this kind of fabric. The period spacing of metallic yarn is the key influencing factors to the SE of the fabric.The SE of the fabrics with metal fbier in one way has significant direction. It is difficult to determine the influence of conductive probability of metal fiber yarn in the junctions and still needs further research. These research results are suitable for electromagnetic shielding fabric, and effective parameters are extracted to quantitative numerical calculating for the shielding effectiveness.