中文摘要：

The authors proposed a plausible explanation for the deviation ofexperimental data for sub-micron polycrystals from the Hall-Perch relation by in-troducing the configuration entropy.The present paper extends the previous two-dimensional analysis to the three-dimensional case.The statistical distribution ofdislocation lengths within a spherical grain and the bow-out of dislocations are con-sidered.According to Ashby’s model,analyses are pursued for the statistically storeddislocations and geometrically necessary dislocations,respectively.It is confirmedthat the configuration entropy model can predict the abnormal Hall-Petch depen-dence for grain sizes in the sub-micron range.

英文摘要：

The authors proposed a plausible explanation for the deviation of experimental data for sub-micron polycrystals from the Hall-Fetch relation by introducing the configuration entropy. The present paper extends the previous two dimensional analysis to the three-dimensional case. The statistical distribution of dislocation lengths within a spherical grain and the bow-out of dislocations are considered. According to Ashby's model, analyses are pursued for the statistically stored dislocations and geometrically necessary dislocations, respectively. It is confirmed that the configuration entropy model can predict the abnormal Hall-Fetch dependence for grain sizes in the sub-micron range.