抄録
The plastic constitutive equation in the random barrier theory can be expressed using two internal state functions which are the plastic potential function and the internal structure variable. The plastic potential function is an another expression of the distribution of barrier strength against the dislocation movement. In this paper, the barrier strength is assumed to be the quantity of the external stress by which an individual slip system can operate at a constant critical resolved shear stress. Simulated specimens consisting of many grains of FCC structure are used for evaluatingg the distribution of barrier strength in polycrystalline metals. It is shown that the Weibull distribution is most suitable for expressing the distribution of barrier intensity. The critical resolved shear stress is found to be the sole factor for regulating the property of the above distribution. The plastic constitutive equation can be described with the activated ratio of the slip system and the internal structure variable.
