快中子照相在武器质量检测中的可行性研究

Feasibility of Fast Neutron Radiography in Weapon Quality Detection

为研究快中子照相技术(FNR)在武器质量检测中的可行性,以公开的武器模型数据建立模拟模型,利用Monte Carlo(MC)方法对快中子照相在武器质量检测中的安全性进行评估,由评估数据得出在14.1 Me V快中子累计照射2×10~8n条件下,铀、钚两种裂变材料损伤极小。同时,参考国外研究模型和预设缺陷,设计加工了类比模型实验样品,通过实验和模拟相结合的方式对武器检测中可能出现的内部狭缝、圆孔和中心位移等问题进行研究。实验结果表明FNR可以识别5 mm钢包裹条件下的1 mm的狭缝缺陷。模拟结果显示FNR可以实现对特定厚度的特殊材料进行中心位移缺陷诊断,模拟评估和实验结果表明快中子照相技术在武器质量检测中具有可行性。

In order to study the feasibility of fast neutron radiography technology(FNR)in weapon quality detection,the research object was established on the basis of the open hypothetical weapon model,and the MC method was used to evaluate the safety of the fast neutron radiography in the weapon quality detection.Results showed that the fissile materials of uranium and plutonium have minimal damage under 14.1 MeV fast neutron irradiation with a total dose of 2×10 8 n.On the basis of referring to the foreign research model and the default defects,the author designed and manufactured the experimental samples,and studied the internal slit,round hole and center displacement which may appear in the weapon inspection by means of both experiments and simulations.The experiment results show that FNR can identify the defects of 1-mm-thick slits inside a steel block of 5 mm thickness.The simulations further show that FNR is able to diagnose the center displacement with certain thicknesses for particular materials.Therefore,our results suggest FNR could be a feasible and potential technique in weapon quality testing.