Study On Perdurable Properties And Design Of Basic Protective Fabric Of Apace Suit

Aiming at the state of development in the out-layer protection materials of EMU(Extravehicular Mobility Unit) or spacesuits, the main purpose in this thesis is to design and develop the out-layer protection materials with high performance fibers and flexible materials, and to provide a series of technical data for the further research of a project. Kevlar and filaments coming from Dupont company and Nomex filaments made in our country have been selected as the samples. The fundamental investigation are the measurement and evaluation for different kinds of protection properties of the materials under the simulated space. It covers the following aspects:i) The fabrication of woven, including the selection of the raw materials, the optimization of the twist parameter, woven structure and weaving technology;ii) The testing and evaluation for the main protection properties of the materials in the assumed space environment: the properties include that of vacuum protection, high and low temperature protection, space radialization protection, debris and meteorite protection. The sealing performance.And iii) The mechanical properties in high temperature and the flexibility in liquid nitrogen are also analysed to evaluate the stability of the fabrics at the extreme temperature environment. According to the results of the reflection, and transmission of spectrum ranges from 250nm to 2500nm, the resistance of the fabric materials to space radialization have been investigated. As far as the protection of debris and meteorite is concerned only at the mechanical properties, the tensile property of fabrics, the tear, puncture and abrasion properties are measured. Meanwhile, the damage taking place in the fabric processing has also been discussed systematically.Through the study, it has been found that the whole design, processing and corresponding are approved from the selection of the raw materials, the yarn processing to the fabric formation and finishing. The 1/3 broken twill is feasible with symmetrical structure and moderate floating-length. According to the analysis of the processing damage, it can be proved that the high utilization coefficient of the materials can be achieved to adopt low deformation ,little wearing and flexible processing.From the whole protection performances of the final products, The thermal resistant of the materials are fine and the low temperature resistant in nitrogen environment is also fine. After the process in the oven the temperature is about 200℃for 10mins, the loss rate of breaking strength and tenacity for the pure yarn fabrics are basically under 12%, and which for the blended fabrics are only 10%, elasticity modulus in liquid nitrogen environment is slightly increased. The property of space radialization protection of materials is not good as expected, both for pure and blend fabrics. In this field the protection effect of and both of them has a severe loss in ultraviolet radiation.The break strength is good while the tear strength is not fine, and the abrasion performance of Kevlar is the promoted by through the blended design.