结构材料核的原子位移截面计算

中子辐照引起的材料损伤是裂变反应堆设计的重要考虑因素。对于晶体结构材料,其辐照损伤主要来自晶格原子的位移。结构材料核与中子发生带电粒子反应的截面、原子位移(DPA)截面、KERMA因子是计算辐照损伤的基础。为比较不同程序计算的DPA截面的差异和基于不同评价核数据库的DPA截面的差异,采用核模型计算程序UNF及核数据处理程序NJOY计算了27 Al、48 Ti、90Zr、Cr、Fe、Ni、Cu等结构材料核的DPA截面,将二者计算结果进行了比较分析;比较分析了基于不同评价核数据库的采用NJOY计算的DPA截面;比较分析了NJOY与蒙特卡罗程序计算的DPA截面。结果表明,UNF与NJOY的结果存在一定的差别,不同评价库的结果也是有差别的,蒙特卡罗程序采用不同模型计算时结果也存在一定的差别。

Calculation of Atom Displacement Cross Section for Structure Material

The neutron radiation damage in material is an important consideration of the reactor design. The radiation damage of materials mainly comes from atom displacements of crystal structure materials. The reaction cross sections of charged particles, cross sections of displacements per atom (DPA) and KERMA are the basis of radiation damage calculation. In order to study the differences of DPA cross sections with different codes and different evaluated nuclear data libraries, the DPA cross sections for structure materials were calculated with UNF and NJOY codes, and the comparisons of results were given. The DPA cross sections from different evaluated nuclear data libraries were compared. And the comparison of DPA cross sections between NJOY and Monte Carlo codes was also done. The results show that the differences among these evaluated nuclear data libraries exist.