DEVELOPMENT AND RESEARCH OF PROTECTIVE PROPERTIES OF MATERIALS FOR BLOCKING ELECTROMAGNETIC RADIATION IN THE INFRARED RANGE

Abstract

Materials for blocking electromagnetic radiation in the infrared range have been developed. The use of boron nitride, chromium oxide, magnetite, which are produced in large quantities by industry, has made it possible to obtain materials suitable for wide application. The basis of the material is a commercially available synthetic textile material. The filler is a synthetic varnish. It has been established that with a minimum content of boron nitride (25 % by weight in one layer), chromium oxide (4.5 %), and magnetite (30 %), the reduction in infrared radiation levels by color temperature is 25-28 %. With the maximum amount of chromium oxide (7.5 %), this figure is 40-45 %. For samples with a magnetite content of 40 % and a minimum content of boron nitride and chromium oxide, the reduction in infrared radiation levels was 75-80 %. At the maximum boron nitride content, this figure increases to 85-90 %, which is acceptable. It is shown that the color temperatures determined by the thermal chamber differ from the actual temperatures of the sample, which is a feature of the chamber design. It is possible to take this fact into account by the calculation method. The corresponding functions include the operating ranges of infrared cameras, the radiation coefficient of the object, the radiation power of the object, etc. This simplifies the process of designing protective materials. Materials have been developed that can be used as thermal camouflage and to solve thermal insulation problems. The use of magnetite as a separate layer in the prototypes made it possible to obtain a shielding coefficient of ultrahigh frequency electromagnetic radiation of the order of 6.0-6.5, which is acceptable for solving problems of electromagnetic compatibility of electronic equipment. The addition of graphite to magnetite in amounts of 1.5-3.0 % increases the shielding coefficients to 8.2-8.5.