Effects of Damage rate on formation of Nano-Precipitates In Reactor Pressure Vessel

研究了Fe-0.3Cu和Fe-0.6Cu两种Fe-Cu二元模型合金在573 K下以3.8×10^<-10>、1.5×10^<-8>和5×10^<-8>pa（位移/原子）/s三种不同损伤速率辐照至约1.6×10^<-2>dpa时Cu沉淀和点缺陷团簇的形成。正电子湮没实验结果表明，在这些辐照下均形成了铜沉淀，且损伤率不同。Cu沉淀物的生长并不随辐照剂量的增加而单调增加，而是取决于微孔的成核和生长。很明显，微孔的成核和生长受到辐照剂量率的影响。

The formation of Cu precipitates and point defect clusters was investigated in two Fe-Cu binary model alloys, Fe-0.3Cu and Fe-0.6Cu, irradiated at 573 K at three different damage rates, namely 3.8×10^<-10>, 1.5×10^<-8> and 5×10^<-8> pa (displacements per atom)/s, up to about 1.6×10^<-2> dpa. Results of positron annihilation experiments indicated that Cu precipitates were formed in these irradiations with different damage rates. The growth of Cu precipitates does not increase monotonously with increasing irradiation dose, but it rather depends on the nucleation and growth of microvoids. It is also clear that the nucleation and growth of microvoids are influenced by the irradiation dose rate.