| The main ideas of this paper are on the basis of study on the establishment of anti-electromagnetic radiation performance tester for textile materials,and its performance study. In this thesis, some simulation modeles of fabric are established, and a series of samples are producd also. Based on the building of series of simulation model samples, the factors of shielding effectiveness and radiation mechanism of different model samples are studied on including the sample of silver-plated blending yarn, filament and sirofil yarn. The relationship between shielding effectiveness and the array density in different interwoven arrangement models is established. Besides, the shielding effectiveness assessment of the blending yarn fabric within short fiber, and the relationship between the content of silver-plated fiber and shielding effectiveness are researched too. Though the designing and woving of anti-eletromagnetic radiation textile used for the environment withing different electromagnetic radiation strength, the shielding effectiveness in different frequency and density is tested ang analied.First, though introducing the research status of test methods to the shielding effectiveness, those related to anti-electromagnetic radiation fabric, knowing that the domestic anti-electromagnetic radiation fabric performance evaluation is also main in qualitative terms, and the foreign equipments can only be used for testing of finished fabric. So according to the shortcomings of existing test methods, a anti-electromagnetic radiation performance tester for textile materials is built, which has considerable advantages, and not only qualitativly test shielding effectiveness and reflectivity accurately for soft and hard flat materials, but also make analog fabric's simulation testing of anti-electromagnetic yarns in different densities and arrangements. It can be used for guiding anti-electromagnetic radiation fabric's development, required in different radiation environment. Based on the tester's successful development, the blindness and lag of development for the anti-electromagnetic radiation textile are deleted, and the development's rapid response mechanism is established, which is"project– designing– optimization– achievement". The development features of high-speed, high-performance and low-cost make it have a wide range application prospects. At present, this tester has applied for national invention patent and utility model patent, the patent application numbers are respectively 200910074176.0 and 200920102167.3, and the later has been authorized. Though a systematic study on the anti-electromagnetic radiation performance tester for textile materials, including testing methods, testing requirements and testing performances, lots important conclusion have been reached as follows, the tester's testing process is fast and simple, which do not need to build expensive room and other auxiliary equipments, moreover the energy loss is small. The testing times is six, which is convenient and quick, reducing the testers'work. The testing errors are mainly from random errors, which can be reduced by increasing testing times. The systematic errors are smaller, the testing accuracy is higher, and has a good reproducibility. The wide dynamic range can be up to 80dB. The testing frequency range is from 30MHz to 3000MHz. The comparison to the testing data of Shanghai testing center's testing equipment, two testing data have good agreement with each other, which show that the anti-electromagnetic radiation performance tester of textile has a higher authority.Based on the testing equipment made by oneself, three kinds of fabric simulation models are established as follows, the model of parallel yarns arranged in one-way, the model of connected interlacing point of yarns at right angle and the model of unconnected interlacing point of yarns at right angle. Though producing samples and the testing and analysing of shielding effectiveness, the kinds of factors effecting shielding effectiveness of fabric are researched. Through the variance analysis, the results show that the density of parallel arrangement in one-way, the density of yarns mesh and the blending ratio of blended yarns of silver-plated fiber/cotton fiber all have significant effect on shielding effectiveness of samples. By the fitting of origin tool, the relation between the diagonal length of mesh and shielding effectiveness is established, which provides a premise to design the fabric with a specific shielding effectiveness rapidly, which comply with the requirements of shielding effectivenes. Though the analysis of variety fitting curves, the diagonal length range of mesh that is economical and practical under the frequency of 2430 MHz is summaried.Though the designing and woving series of silver-plated fiber fabric, ang the comparison between the testing data of fabric and theoretical data of simulation samples, the results show that the change trends of the two data with different density of silver-plated is similar in the same radiation frequency. The phenomenon was analized,which is that testing data is bigger than the theoretical data or smaller than it sometimes in the certain degree of frequency and density (or the diagonal length). In addition, the concept is realized, which is the shielding effectiveness of simulation model samples guiding the designing and development of anti- electromagnetic radiation fabric has been proved.Though the study on the content of silver-plated fiber having significant effect on shielding effectiveness of fabric by variance analysis, the scatter plot between the content of silver-plated and shielding effectiveness, and the relation are established.In paper, the fabric of silver-plated are made for desizing by hydrogen peroxide desizing. The technic is that 90℃boiled for 30 minutes, then washed with water to neutral, the last dried in 100℃. By the comparison between the shielding effectiveness of before and after desizing, the results show that the two shielding effectiveness are similar, that is to see that the effect of hydrogen peroxide desizing to shielding effectiveness can be ignored.
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