Heavy ion irradiation of 80 mev 12c or 85 mev 19f is used to simulate the proton and neutron irradiation of the beam window materials for ads . the irradiation effects are examined by the positron annihilation lifetime technique 在ads散裂中子源束窗材料辐照效应研究中,使用80mev的~ ( 12 ) c或85mev ~ ( 19 ) f离子模拟中子及质子辐照在束窗材料中产生的辐照损伤。
In czochralski silicon crystals ( czsi ) through fast neutron irradiation , formation and conversion of defects were investigated using fourier transform infrared spectroscopy ( ftir ) , positron annihilation technology ( pat ) and scanning electron microscope ( sem ) . the results showed that fast neutron irradiation induced large quantity of metastable defects which can be the capture centers of positron , positron annihilation average lifetime of samples increased with increasing of irradiation dosage . positron annihilation average lifetime of irradiation samples through dosage up to 1 1018 n . cm - 2 tended to constant 本文对直拉硅样品进行了不同剂量的快中子辐照,在硅中引入大量的亚稳态缺陷,研究这些亚稳态缺陷的形成,并在较宽的温度范围内对辐照样品进行了退火处理,研究退火后亚稳态缺陷的转化及同硅中氧的相互作用,应用傅立叶变换红外光谱技术( ftir ) 、正电子湮没技术( pat )和扫描电镜( sem )进行了测试。
Radiation effects have been investigated up to - 30 dpa by the heavy ion irradiation simulation and positron annihilation lifetime techniques in the home - made modified 316l stainless steel and the commercially available stainless steel and tungsten , which are used as the beam window materials for the spallation neutron source in accelerator driven radioactive clean nuclear power system ( ads ) . their radiation resistance properties are compared 本工作采用重离子辐照模拟和正电子湮没寿命测量技术研究了加速器驱动洁净能源系统( ads )散裂中子源束窗材料钨、普通不锈钢和国产改进型316l奥氏体不锈钢在0 30dpa辐照剂量范围的辐照效应,并对它们的抗辐照性能作了比较。
After annealing at 600 , because of formation of multi - vacancy - type defects that have long positron lifetime , positron annihilation average lifetime increased . when the average positron lifetime increased to maximum value ( 360ps ) , the interstitial oxygen concentration decreased to minimum value ( 4 1017atoms / cm3 ) . this result suggested that oxygen was involved in the formation of multi - vacancy - type defects 正电子湮没技术测试证明,快中子辐照直拉硅中在大约600退火时产生的多空位缺陷具有较长正电子寿命,可以使正电子平均寿命增加,当样品的正电子平均寿命达到最大时( 360ps ) ,其间隙氧含量降到一个极小值( 4 10 ~ ( 17 ) atoms / cm ~ 3 ) ,这说明氧参与了这些缺陷的形成。