| The rupture of paper is controlled not by the mean strength, but by the minimum strength regions in the sheet. In order to fully understand which aspect of structure controls these weak regions and their effect on the local strength of paper, an effort was made to correlate variations in two microstructural features (fibre orientation and bonded area) of the sheet with the variability of local properties. The objective of this study was to identify if the structure varied significantly from point to point and to attempt to correlate the structural features of paper with properties in a deterministic way. By using a new analytical method for the estimation of fibre orientation, a relatively strong correlation was observed between local variation in mean fibre orientation and the local strength of paper. By considering fibre orientation and bonding simultaneously, a relative strength model was developed in this study in order to improve the correlation between local tensile strength and local structure. |
