Static and dynamic failure mechanisms of cotton yarns

Abstract

The effect of various material and testing parameters on the static and dynamic failure mechanisms of cotton ring yarns of several counts has been studied. The yarn broken ends are classified into three groups, namely sharp, taper and slipped ends, based on their captured breaking zone images. The percentage of sharp broken ends increases with the increase in yarn TM and yarn count; however the rate of increase is quite low in dynamic testing. The interaction effect of yarn TM and yarn count in static failure mechanism is also studied. It is observed that the yarn count is dominating the yarn TM in deciding the percentage of sharp broken ends. The interactive effect of yarn TM, yarn count and dynamic testing speed is characterized along with their individual influence on the dynamic failure mechanism. It is observed that the effect of yarn TM is dominating the yarn failure mechanism than other influencing factors. The comparison of static and dynamic yarn strength is carried out to assess the over estimation of static yarn strength. This difference in two types of strength can be attributed to the difference in their failure mechanisms and length of yarn over which strength is measured.