Author :
Gharehaghaji, A. A.,Johnson, N. A. G.
Abstract :
The possible modes of deformation and microdamage due to contact stresses have been studied quantitatively on sigle wool fibres compressed against opening elements by extending a fibre looped around the element. By using scanning electron microscopy, the contact area of test fibres has been studied to assess the surface morphology caused by localised contact stresses built up at the contact area. The study showed that compressive stresses are built up over the contact area. Also,longitudinal and transverse cracks created in high speed sliver opening experiments,as reported in Part 1 of this series [1],were successfully reproduced in this controlled experiment. The cracks and comperssive stresses observed strongly suggest the involvement of llertzian contact stresses in ultimate fibre rupture. The effect of the rate of strain on fibre microdamage is discussed.
