锆基合金中子辐照损伤模拟的初设条件优化
分子动力学(Molecular dynamics,MD)是研究材料原子尺度结构及其变化的重要模拟方法,可用于模拟材料的粒子辐照损伤。由于该方法不包含核数据,通常对初始化条件进行简化处理,如初级撞出原子(Primary Knock-onAtom,PKA)的条件设定和材料结构模型的建立。采用粒子输运软件GEANT4模拟中子辐照Zr、Zr2Cu和Zr2Ni,得到其PKA能谱,发现不同能量入射中子对应的PKA最高能量可达几十甚至几百keV,且三种材料中PKA能谱非常接近。计算三种zr基合金的PKA数目,发现其分布非常接近,表明分子动力学模拟时可采用简化结构模型,以研究zr基合金、Fe基合金;此外,计算...
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          | Published in | 核技术 Vol. 40; no. 2; pp. 13 - 18 | 
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| Main Author | |
| Format | Journal Article | 
| Language | Chinese | 
| Published | 
            南京航空航天大学材料科学与技术学院 南京 211106
    
        2017
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| Subjects | |
| Online Access | Get full text | 
| ISSN | 0253-3219 | 
| DOI | 10.11889/j.0253-3219.2017.hjs.40.020202 | 
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| Summary: | 分子动力学(Molecular dynamics,MD)是研究材料原子尺度结构及其变化的重要模拟方法,可用于模拟材料的粒子辐照损伤。由于该方法不包含核数据,通常对初始化条件进行简化处理,如初级撞出原子(Primary Knock-onAtom,PKA)的条件设定和材料结构模型的建立。采用粒子输运软件GEANT4模拟中子辐照Zr、Zr2Cu和Zr2Ni,得到其PKA能谱,发现不同能量入射中子对应的PKA最高能量可达几十甚至几百keV,且三种材料中PKA能谱非常接近。计算三种zr基合金的PKA数目,发现其分布非常接近,表明分子动力学模拟时可采用简化结构模型,以研究zr基合金、Fe基合金;此外,计算了PKA散射角,获得不同能量中子产生的PKA最佳散射角,为分子动力学模拟所需的PKA运动方向提供理论依据。 | 
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| Bibliography: | Background: Molecular dynamic (MD) method has been widely used in simulation of particle radiation-induced micro-structure damage in materials. There is no nuclear database in MD simulation, thus, simplified processing is adopted in some initial conditions, such as primary knock-on atom (PKA) and structural model of the material. Purpose: This study aims to obtain the optimal initial conditions for MD to simulate the particle radiation-induced structural damage. Methods: GEANT4 software was applied for simulating neutron radiating Zr-based metals (Zr, Zr2Cu and Zr2Ni). The PKA spectra excited by incident neutrons were tracked and detected. Thereafter the PKA scattering angel distribution was calculated. Results: It is found that PKA energy in these three metals increases with the neutron energy, and exists a cut off value of dozens or hundreds keV. In addition, it is revealed that the PKA energy spectra in these three metals are very similar. The preferred scattering angles of PKAs were estimated. Conclusion: | 
| ISSN: | 0253-3219 | 
| DOI: | 10.11889/j.0253-3219.2017.hjs.40.020202 |