Fabricação de malha de trama utilizada como pré-formas na indústria de compósitos e avaliação das propriedades mecânicas

摘要

In the manufacture of composite, textile materials are being used as reinforcement. Generally, the combination of the matrix with the textile material in the form of fibres or yarns is used depending on their distribution in the web. In the present work, in place of fibres or yarns, a knitted structure in the form of the final product which is defined as preform. The preform is weft knit manufactured with polyester filaments. In the manufacture of composite, polyester resin was used as matrix. The physical and mechanical properties as well as the formability of the weft knit were analysed. The physical and mechanical properties as well as theformability of the knitted structure were analysed. The results obtained on the analysis show that the courses and wales of the weft knit structure and the tensile properties help the formability of the structure and the impregnation of the resin. It could be clearly observed that composite structure in the direction of the courses support more tension than in the direction of the wales. In relation to the three pointsflexural tests it was possible to note that there was more flexion in the direction of wales, what was expected. It was also possible to note that there are other advantages such as reduction in the loss of materials used, homogeneity in thedistribution of the knitted structure in the mould, reduction in the preparation time and also in the reduction in the cost of manufacture