利用蒙特卡罗程序EGSnrc实现电子束辐照剂量分布的计算和电子束辐射加工工艺的优化

APPLICATIONS OF EGSnrc MONTE CARLO SYSTEM IN CALCULATIONS OF DOSE DISTRIBUTION IN MATERIALS IRRADIATED BY ELECTRON BEAM AND OPTIMIZATION OF ELECTRON RADIATION PROCESSING

利用蒙特卡罗程序EGS4的最新版本EGSnrc ,在Linux操作系统平台上计算了在 1.5- 3.0MeV能量范围内电子在聚乙烯材料和水中的剂量深度分布 ;比较了在两种不同厚度的聚乙烯板的底部加上不同材料 (铝、铜、铅 )衬底情况下剂量深度分布的变化 ;计算了电子束在入射到聚乙烯材料之前经过的空气层的厚度对剂量损失的影响及不同电子束射野大小对剂量分布的影响。计算的结果以绝对剂量的形式给出 ,误差在 2 %以内。该方法是优化电子束辐射加工工艺的一种实用、高效的理论估算方法。

The dose distribution in polyethylene and H 2O were calculated by a new EGS4 version-EGSnrc Monte Carlo code system with 1.5MeV-3MeV initial electron energy. The effects of different metal base-plate such as Al?Cu and Pb for dose depth profile in materials were compared. And the effects of different electron beam size on absorbed dose were calculated, too. The dose was given by absolute dose (Gy.cm 2). The calculation uncertainty was controlled within 2%. This kind of work proposes a useful theoretical tool for optimizing technology of electron radiation processing.