ANALYSIS OF THE EFFECT OF GRAIN-SIZE UNIFORMITY ON THE FLOW-STRESS OF POLYCRYSTALS .2. APPLICATION OF THE STUDIES TO THE FLOW-STRESS OF ALUMINUM

The method described in Part I has been used to estimate the standard deviation of grain volumes for a series of Al specimens. The specimens were used earlier for the studies of the Hall-Petch (HP) relationship. Detailed measurements showed that the specimens are geometrically incompatible. The effect is demonstrated by the variation in the values of SD(lnV). It is shown, however, that the differences in the value of SD(lnV) are too small to account for the variations in the value of HP constants. This finding points the way for interpretations of the effect in terms of varying physical properties of the grain boundaries and the grain interiors. General analysis on the approach to the geometrical description of the grains required for the consistency of the HP constants is given.