压力容器模型钢中富MnNi沉淀籽核构型探究

Study on Configuration of Nuclei for MnNi-Enriched Precipitation in Model Reactor Pressure Vessel Steels

富Mn Ni沉淀(MNP)是低Cu压力容器钢(如A508-Ⅲ钢)在高剂量(如60~80 a寿期剂量)下引起脆化的主要因素之一,用分子静力学(MS)计算了溶质及缺陷之间的结合能与形成能,依据能量最低原理找出2类可能形成MNP的籽核构型:空位型籽核和间隙型籽核,其中空位型籽核为Cu-空位复合体(Cu-nVac,n≥3);间隙型籽核为混合型FeMn<110>-X(X为Mn、Ni或Cu等)复合体。

It has been justified that Mn Ni-enriched precipitation(MNP) is an important contribution to the embrittlement of low-alloyed reactor pressure vessel(RPV) steels(like A508 III steel) when irradiated to high dose in like 60 to 80 years. In this paper the Molecular Statics method was used to calculate the binding energy and formation energy among solutes and defects, so as to find out the possible nuclei of MNP with the lowest energy, which might be classified into two kinds of complexes, one composed by Cu and several(≥3) vacancies and the other mixed FeMn<110> dumbbell with Mn, Ni or Cu atoms trapped.