Objective to understand the 5% boron polyethylene (atomic number %) shielding fast neutron shielding effect, use californium - 252 (^ 252 cf) and americium - beryllium (241 am - Be ^) standard neutron source, respectively for the fast neutron shielding is studied in this protective effect. Method 3. The 2cm thick boron polyethylene plate is cut in diameter 5. 5cm, thickness of 3. Superposition of 2 cm round to test samples, the samples for different thickness of ionizing radiation in the national defense science and technology industry - level metering station with 252 cf and ^ ^ 241 am - Be standard neutron source illuminate, the boron polyethylene slabs with different thickness were measured the fast neutron transmittance. The results showed that the thickness of boron polyethylene plate was 3. 2 cm, to ^ 241 am - Be source of neutron shielding efficiency of 47. 7% of ^ 252 cf source neutron shielding efficiency is 60%, the boron polyethylene plate thickness to 12. 8 cm, to ^ 241 am - Be source neutron shielding efficiency was 91%, that's right. 252 ^ 252 cf source neutron shielding efficiency. 5%, the thickness of the boron polyethylene plate is 22. 4 cm, on ^ 241 am - Be source of neutron shielding efficiency for 97. 9%, to 252 ^ 252 cf neutron shielding efficiency of the source. 2%. Conclusion the boron polyethylene plate is an efficient neutron shielding material for neutron and neutron radiation shielding. 

    目的为了解5％含硼聚乙烯（原子数％）屏蔽快中子的防护效果，用锎-252（^252Cf）和镅-铍（^241Am—Be）标准中子源分别对其屏蔽快中子的防护效果进行了实验研究。方法将3．2cm厚的含硼聚乙烯板裁成直径5．5cm，厚度3．2cm的圆形待测样品，叠加为不同的样品厚度，在国防科技工业电离辐射-级计量站用^252Cf和^241Am—Be标准中子源照射，分别测量不同厚度的含硼聚乙烯板对其快中子的透射率。结果结果表明，该含硼聚乙烯板厚度为3．2cm时，对^241Am—Be源中子屏蔽效率为47．7％，对^252Cf源中子屏蔽效率60％，该含硼聚乙烯板厚度为12．8cm时，对^241Am—Be源中子屏蔽效率为91％，对。^252Cf源中子屏蔽效率95．5％，该含硼聚乙烯板厚度为22．4cm时，对^241Am—Be源中子屏蔽效率为97．9％，对^252Cf源的中子屏蔽效率98．2％。结论该含硼聚乙烯板是-种高效的防中子屏蔽材料，可有效用于中子和中子、γ混合辐射场中的中子辐射屏蔽防护。