新型涂硼正比计数器研制及其实验测试和模拟计算  

Development of New Type Boron-coating Proportional Counter and Its Experimental Investigation and Simulation Calculation

作　　者：张紫霞[1] 魏志勇[2] 朱立[3] 方美华[2] 陈国云[4] 强鹏[2] 

机构地区：[1]南京航空航天大学材料科学与技术学院,江苏南京210016 [2]南京航空航天大学航天学院,江苏南京210016 [3]中国船舶重工集团公司第七零五研究所,云南昆明650118 [4]南昌大学理学院,江西南昌330031

出　　处：《原子能科学技术》2015年第3期545-551,共7页Atomic Energy Science and Technology

基　　金：江苏省普通高校研究生科研创新计划资助项目(CXLX11_0192);中央高校基本科研业务费专项资金资助项目(NS2012070)

摘　　要：本文将^10 B粉与1,2-二氯乙烷溶剂、芳华树脂粘结剂混合研制了中子灵敏层^10 B膜,以此制作一新型涂硼正比计数器。为增加探测效率,除管内壁涂硼外,在管内增置了14片双面涂硼环氧薄片,并用^241 Am-Be源测试了其性能。活度为3.7×10^9 Bq的^241 Am-Be源实验表明：此新型涂硼正比计数器坪长约150V,坪斜为8.2%/100V（750-900V）;工作电压为800V时测得新型涂硼正比计数器的计数率为50s^-1,灵敏度为0.71cm^2。与管内壁仅涂硼的正比计数器相比,新型涂硼正比计数器中子灵敏面积增加到3.15倍后,探测器坪长从80 V增至150 V,坪斜从12.4%/100 V改进到7.58%/100V,灵敏度提高到2.63倍。同时,以基于蒙特卡罗方法的Geant4平台,模拟计算单能中子及^241 Am-Be源中子照射包裹高密度聚乙烯慢化材料的新型涂硼正比计数器的响应和探测效率。^241 AmBe源模拟结果和实验结果吻合较好。实验测试及模拟结果表明,涂硼技术与增加灵敏面积相结合的正比计数器的设计较成功。Three materials wherein suitable proportion of isotope enriched 10B powder , 1 ,2‐ethylene dichloride and formvar resin were blended to make ^10B neutron sensitive coating by oneself .A new type proportional counter that coated with ^10 B neutron sensi‐tive coating was made .Furthermore ,in order to increase the character and quality of the neutron detector ,a set of 14 annulus epoxy sheets which were sided with ^10B film were placed in the tube .A series performance tests were done by ^241 Am‐Be neutron source .The tests of 3.7 × 10^9 Bq ^241 Am‐Be neutron source show that the plateau length of detector is 150 V from 750 V to 900 V ,while the plateau slope is 8.2% /100 V . When the working voltage is 800 V ,the count rate of new type boron‐coating propor‐tional counter is 50 s^-1 . The level of sensitivity is 0.71 cm^2 . Compared with the detector only coated with ^10B film in the inner walls of detector ,neutron sensitity area of the new detector increases to 3.15 times . The results show that the plateau length increases from 80 V to 150 V ,and the plateau slope is improved from 12.4% /100 V to 7.58% /100 V ,while the neutron sensitivity increases to 2.63 times . Using Geant4 software based on Monte Carlo method ,this paper presented the response and detection efficiency of new type boron‐coating proportional counter , which was covered with φ55 mm ×250 mm cylinder high density polyethylene moderator material .The simula‐tion results of Geant4 are in agreement with the results of ^241 Am‐Be neutron source experiment .It show s the reliability of simulation application .

关 键 词：中子 涂硼正比计数器 坪曲线 探测效率 

分 类 号：TL816.3[核科学技术—核技术及应用]