چكيده لاتين :
The mechanical properties of plain woven fabrics have been investigated under
ten9ile fatigue. It is proposed that the mechanism of their fatigue consists of two
stages: yarn slippage in the fabric and yarn elongation. The yarn slippage in the
fabric occurs at the initial stage of fatigue. This mechanism which arises from interyarn
friction in the fabric structure causes sharp variations in the fabric viscoelastic properties.
Finally the region of the steady variations of the fabric viscoelastic properties
seems to be due to yarn elongation. In this study plain woven fabrics were produced
with different weft density and their viscoelastic properties have been analyzed by the
dynamic mechanical analyzing technique at two different strains and frequencies. It is
found that by increasing weft density, the fabric storage modulus and loss modulus
increase for all testing conditions, while damping factor decreases at 0.5% strain and
1 Hz frequency. No particular trend was observed in the variations of fabric percentage
elongation versus weave density. It has been demonstrated that fabrics at low
strain have shown better recovery from extension and greater stability against repeated
tensile fatigue, but an increase in lifetime when frequency was increased.
