基于氦泡与位错密度演化的老化δ-Pu静力学本构模型  

Static Constitutive Model of Aged δ-Pu Based on Evolution of Helium Bubbles and Dislocation Density

作　　者：晏顺坪 余勇[1] 王沪毅[1] 赵丰鹏 

机构地区：[1]中国工程物理研究院,总体工程研究所,四川绵阳621900

出　　处：《物理化学学报》2015年第B05期59-63,共5页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金（11302209）与国家自然科学基金委员会和中国工程物理研究院联合基金（u1330121）资助项目

摘　　要：δ-Pu材料由于钚元素a衰变发生自辐照老化，随着老化时间增加，材料微结构和宏观力学性质发生变化．氦泡作为自辐照的主要产物，通过阻碍位错运动实现对δ-Pu力学性质的影响．文中首先通过钚材料级联衰变规律建立氦泡体积分数与老化时间的关系，然后将氦泡对位错运动临界剪切应力的影响和氦泡长大规律引入本构方程，获得基于位错密度演化的δ-Pu静力学本构方程组．拟合实验数据得到本构模型参数．最后，通过模型计算获得不同老化时间下δ-Pu的应力应变关系．The o radioactive decay of Pu by self-irradiation in the δ-Pu alloy markedly changes its microstructure and macro mechanical properties. Helium bubbles, the main product of self-irradiation, can affect the plastic behavior of δ-Pu by impeding the movement of dislocations. In this paper, we first derive a relationship between the volume ratio of helium bubbles and aged time. We then introduce the effect of helium bubbles on the critical resolved shear stress for dislocation motion and the growth law for helium bubbles into a constitutive model to obtain the dislocation-based static constitutive functions of δ-Pu. Model parameters are then fitted using experiment data. Finally, the stress-strain curves of δ-Pu for different aged times are presented.

关 键 词：δ-Pu 自辐照 氦泡 本构模型 

分 类 号：O642[理学—物理化学]