engleski

Investigation of Tensile Forces in two Directions in Stitched Fabrics

Wool fabrics for police uniforms require a certain strength and elasticity. In this paper the resistance of woven fabrics to straining in different directions was investigated. The test was preformed in a way that both directions were observed for the same period of time. This property is of great importance for fabrics for this usage. This study continues on previous investigations in which the impacts of the seam on mechanical properties of fabrics in warp and weft directions were investigated. Testing of mechanical properties of fabrics was carried out according to standard HRN EN ISO 13935-1:2008. Samples of a fabric stitched with two stitch densities and two needle sizes were tested. Additional testing of mechanical properties of fabrics were also preformed, using nonstandard method where lateral contraction and force were measured during testing of longitudinal extension to rupture. For this purpose, the new innovative instrument, installed on the conventional tensile strength tester, were used. It was found that mechanical properties of fabrics vary depending on stitch type, needle size and the shape of the sample. Furthermore, the changes in lateral contraction and lateral forces during longitudinal extension to rupture were also found. Test results of breaking force and lateral force for all samples shows a high degree of correlation.

lateral contraction of the fabrics; mechanical properties of sewn fabrics; tensile strength tester; wool fabric; seam

nije evidentirano