The mechanical properties,thermodynamic properties and electronic structure of Mo1-xTax(Mo-Ta)alloys(x=0,0.0625,0.125,0.25,0.3125,0.5 and 1)were calculated by using firstprinciples.The electronic structure of Mo-Ta al...The mechanical properties,thermodynamic properties and electronic structure of Mo1-xTax(Mo-Ta)alloys(x=0,0.0625,0.125,0.25,0.3125,0.5 and 1)were calculated by using firstprinciples.The electronic structure of Mo-Ta alloys was analysed by the projected density of states(PDOS).The low temperature heat capacity was estimated by Fermi energy and Debye temperature.It is shown that the formation enthalpy will decrease with the increase of Ta content,and the cohesive energy will increase with the increase of the Ta content.On the other hand,the addition of Ta atoms will reduce the strength and improve the ductility of Mo-Ta alloys,the Debye temperature will decrease and the low temperature heat capacity will be improved with the increase of the Ta content.All these results will be useful for the research of new plasma grid(PG)materials,which is mainly used in neutral beam injection(NBI)systems to produce negative hydrogen ions.展开更多
Mo-Ta合金作为一种有高熔点、抗辐照等特点的材料,被视为聚变工程中制造第一壁的潜在材料。目前有关Mo-Ta合金与H杂质相互作用的研究还不完善,本文研究了H杂质在体心立方Mo53Ta_(1)合金中间隙位置的成键机制。通过基于密度泛函的第一性...Mo-Ta合金作为一种有高熔点、抗辐照等特点的材料,被视为聚变工程中制造第一壁的潜在材料。目前有关Mo-Ta合金与H杂质相互作用的研究还不完善,本文研究了H杂质在体心立方Mo53Ta_(1)合金中间隙位置的成键机制。通过基于密度泛函的第一性原理方法,通过Material Studio的CASTEP(Cambridge Serial Total Energy Package)模块计算了Mo53Ta_(1)-H体系的溶解能,态密度与布居数。溶解能计算结果表明:H原子在Mo-Ta合金中更倾向于存在与四面体间隙位置;通过分波态密度与布居数,分析了H、Mo、Ta之间不同电子轨道间电子转移情况与不同原子间的成键情况。得出Mo、Ta间为金属键,H与Ta和Mo之间存在共价作用,且H与Ta之间的共价作用更强。展开更多
基金supported by National Natural Science Foundation of China(No.11820101004)the National Key R&D Program of China(2017YFE0300100,2017YFE0301100)。
文摘The mechanical properties,thermodynamic properties and electronic structure of Mo1-xTax(Mo-Ta)alloys(x=0,0.0625,0.125,0.25,0.3125,0.5 and 1)were calculated by using firstprinciples.The electronic structure of Mo-Ta alloys was analysed by the projected density of states(PDOS).The low temperature heat capacity was estimated by Fermi energy and Debye temperature.It is shown that the formation enthalpy will decrease with the increase of Ta content,and the cohesive energy will increase with the increase of the Ta content.On the other hand,the addition of Ta atoms will reduce the strength and improve the ductility of Mo-Ta alloys,the Debye temperature will decrease and the low temperature heat capacity will be improved with the increase of the Ta content.All these results will be useful for the research of new plasma grid(PG)materials,which is mainly used in neutral beam injection(NBI)systems to produce negative hydrogen ions.
文摘Mo-Ta合金作为一种有高熔点、抗辐照等特点的材料,被视为聚变工程中制造第一壁的潜在材料。目前有关Mo-Ta合金与H杂质相互作用的研究还不完善,本文研究了H杂质在体心立方Mo53Ta_(1)合金中间隙位置的成键机制。通过基于密度泛函的第一性原理方法,通过Material Studio的CASTEP(Cambridge Serial Total Energy Package)模块计算了Mo53Ta_(1)-H体系的溶解能,态密度与布居数。溶解能计算结果表明:H原子在Mo-Ta合金中更倾向于存在与四面体间隙位置;通过分波态密度与布居数,分析了H、Mo、Ta之间不同电子轨道间电子转移情况与不同原子间的成键情况。得出Mo、Ta间为金属键,H与Ta和Mo之间存在共价作用,且H与Ta之间的共价作用更强。
