Mechanical Performances Of The Tenting Flexible Composites

As one of the three biggest applied fields of the textile fabrics, industrial textile fabrics are advancing very quickly. In the present world, most production technologies of industrial textile fabrics are traditional weaving technique. In all the industrial textile fabrics, woven fabrics roughly account for 50%, non-woven fabrics account for 40% while warp-knitted fabrics only account for a very small rate. However, warp-knitted fabrics have many advantages which act as composites better and can be produced efficiently, so they have been catching more and more attention, their developing momentum is very strong, and they are taking the places of other products step by step.In this thesis we mainly studied some mechanical performances of the tenting flexible composites, in which there are mainly two substrates: woven fabrics and warp-knitted bi-axial fabrics. We compared the two composites by analyzing the testing data and then summarized the factors affecting the mechanical performances of the tenting flexible composites. Additionally, we made more comparisons between different testing standards and gave forward some effective suggestion. This is a good promotion and reference for establishing our national testing standards of the mechanical performances of the homogeneous products, and meanwhile it has good technical instructive significance for the practical production of the homogeneous products.During the course of the research, we collected a quantity of testing samples, including: different yarn counts, different fabric density, different fabric structures, different ways of fabric finishing: coating, calendering and laminating. In this thesis we mainly studied theirmechanical properties, compared and analyzed the testing data, as well as the determination of the parameters such as the mass per unit area, density, thickness of the fabrics.First, we did the tensile experiments on the two types of flexible composites, compared and analyzed the testing data, summarized several factors affecting the tensile strength, and finally drew the conclusions. That is, the tensile strength of warp-knitted bi-axial fabrics is improved a lot because directly oriented parallel and noncrimped yarns are inserted into the structures. Furthermore, the availability of the mechanical properties of yarns is quite high, which makes it possible to reduce the density of the fabric and therefore reduce the mass of fabric when the whole high strength of fabric is still ensured. Economically, with this excellent tensile performance, we can dramatically save raw materials and reduce the production cost.Second, we further studied and compared the tear performances of the two types of flexible composites and summarized several factors affecting the tear performance. We confirmed that warp-knitted bi-axial fabrics are superior to woven fabrics in tearing when used as the substrates of tenting flexible composites. We also studied the linear relationship between the tensile and tear performance of the flexible composites. At the same time, we researched and compared the domestic and foreign tear testing standards, trying to find out the internal parametric relationship among them, in order that the researchers can simply and conveniently transfer and compare the data which are obtained under the different testing standards. Besides, we put forward some suggestion on how to do the tear experiment on flexible composites more effectively and practically.Third, we tested the peeling performances of the two types of flexible composites. The peeling performance is another importantparameter index as well as the tear performance. Here we studied the effects which the different ways of finishing cause. However, the peeling test is very difficult to carry out because of the limited testing conditions, so here we referred the technical data of the concerned companies.In this thesis, however, there are still some shortages that should be improved in the future. At the end of this thesis we foresaw the developing prosp...