| Popis: |
Merino, Corriedale, and Lincoln wools for use in basic research have been grown by the C.S.I.R.O. Sheep Biology Laboratory in Australia under conditions designed to produce wools which are as uniform as possible in physical and chemical properties. The uniformity of fibre thickness along the length of the fibres is examined and its influence on experimental measurements of mechanical elastic constants, particularly breaking stress, is considered. A stress factor which can be applied as a correction to the usual estimate of breaking stress based on mean cross-sectional area of single fibres is proposed. The regularity along the length of the Merino wool first produced was twice that of field-grown wool. More recently, wools have been produced with a coefficient of variaiton of cross-sectional area along the length of the fibre of 7% compared with 27% for field-grown wool. For the most uniform Merino wool used, the breaking stress calculated on mean cross-sectional area should be multiplied by 1·10 to give ... |
