Research on the Breaking and Tearing Strengths and Elongation of Automobile Seat Cover Fabrics

The automotive industry is a major customer of the technical textiles market. In this industry, seat covers are the most important application area of technical textiles. As the customer demands increase and competition among original equipment manufacturers (OEMs) becomes more intense, the test standards for technical textiles are gradually being raised and becoming more thorough. Higher breaking and tearing strengths and breaking elongation are specifications required for advanced seat covers. It is a fact that deficiencies in these specifications have some effect on field returns (the return of failed cars to field service), raising costs and loss of confidence in the product and the producer. This paper investigates breaking and tearing strengths, and breaking elongation performances of the technical textiles used for automobile seat covers. The fabrics used in this research were supplied from seat cover fabric manufacturers who produce these fabrics for multinational automotive companies. The data obtained from the tests are evaluated statistically. The results indicate that flat woven and woven velour seat cover fabrics are the best in terms of breaking and tearing strength performances. Circular knitted automobile seat cover fabrics give the greatest elongation measures

Development of novel auxetic textile structures using high performance fibres

The present work reports the first attempt of developing auxetic structures using high performance fibres through knitting technology. Polyamide (PA) and para-aramid (p-AR) fibres and their combination were knitted in to purl structures using flatbed knitting machine, varying different structural (such as loop length, cover factor and yarn density) and machine parameters (such as take-down load). The influence of different parameters on negative Poisson's ratio (NPR) was thoroughly investigated. It was observed that NPR improved strongly with the increase in loop length of knitted structures. NPR also increased withthe decrease in cover factor and increase in course density of knitted fabrics. An increase in take-down load also improved NPR for tightly knitted samples, but led to initial decrease and subsequent increase in NPR for medium and higher loop lengths; except for p-AR fabrics, which showed a decrease in NPR with take-down load for higher loop lengths. Tensile properties of the developed auxetic structures were also found to depend strongly on fibre type and loop length, and the highest tensile performance was achieved with lower loop lengths and p-AR yarns. The p-AR fabrics produced using lower loop length and lower take-down load resulted in the highest NPR of−0.713. Therefore, the developed knitted structures produced using high performance yarns and showing strong auxetic effects can have huge potential for industrial applications, especially in personal protection materials, such as cut resistance fabrics, bullet proof vest, helmets, and so on.CAPES Foundation, Ministry of Education of Brazil - grant BEX 0978/12-

Strengthening masonry vaults with organic and inorganic composites:An experimental approach

Polymer-reinforced fibers are now commonly applied to buildings for structural retrofitting purposes. These materials add greater tensile strength to structures, at the expense of a slight increase in weight. However, they also have other disadvantages such as brittle behavior and lack of water vapor permeability, which are not desired in the conservation of heritage buildings. Alternative composite materials embedded in an inorganic matrix are presented, which solve some of the drawbacks associated with organic matrices. Long steel fibers and basalt textiles are applied to the resistant core of the inorganic matrix to produce a steel-basalt reinforced mortar-based composite. Firstly, a mechanical characterization of the individual components and the resulting material was performed. Secondly, non-strengthened and strengthened real-scale (2.98 m span, 1.46 m high and 0.77 m deep) brick masonry vaults were tested up to failure, in order to demonstrate the mechanical effectiveness of these composite materials. Finally, a comparison between two mortar composite materials (steel-strips/basalt-textiles embedded in a polymer matrix) was performed, with the same real-scale brick-vault failure tests. The experimental campaign demonstrates that the steel/basalt composite mortar is a feasible alternative, which is physically compatible with masonry structures, easy to apply, and effective for the reinforcement of brick vaults.This research work was made possible thanks to finances from the EFFESUS Collaborative Project FP7 (G.A. No. 314678) and the Basque Regional Government (IT781-13 research group). Furthermore, the authors wish to thank Javier Bengoechea, Josu Lucena, Stamatios Mihos, Vasileos Plamantouras and Antonio de Arcos for their kind contributions to this research work