钨/石墨烯/钨面向等离子体复合材料力学与热学及耐辐照性能衰减的第一性原理计算

通过第一性原理计算研究了钨/石墨烯/钨复合材料相比于纯钨金属在力学与热学性质方面的变化，并用氦原子-空位缔合缺陷模拟核聚变辐照损伤评估等离子体辐照条件下的性能。计算结果表明：钨/石墨烯/钨复合材料的体积弹性模量、杨氏模量与剪切模量呈现一定程度的下降，但是提升了钨基材料的延展性；钨/石墨烯/钨复合材料的热膨胀系数有所增加，但是具有较高的最小热导率。本文阐述了石墨烯界面层可以对基体杂质与缺陷进行吸附的独特机制，通过这种机制，钨/石墨烯/钨复合材料在力学、热膨胀系数以及最小热导率有更低程度的衰减，这显示了钨/石墨烯/钨复合材料在抗辐照性能方面具有较大的应用潜力。

First-Principles Calculations about mechanical and thermal Properties and Radiation Resistant of tungsten/graphene/tungsten Composite as Plasma Facing Materials

First-principles calculations were conducted to investigate the changes in mechanical and thermal properties of tungsten/graphene/tungsten composites, and the performance attenuation under plasma irradiation was evaluated via simulated irradiation damage by helium-vacancy associative defect. The calculation results show that the bulk modulus, Young''s modulus and shear modulus of the tungsten/graphene/tungsten composites decrease to a certain extent, but the ductility is improved. The tungsten/graphene/tungsten composites increase thermal expansion coefficient at high temperatures compared with pure tungsten, but have a higher minimum thermal conductivity. The unique mechanism by the graphene interface layer can absorb impurities and defects in the matrix, which can result in tungsten/graphene/tungsten composite has smaller attenuation in mechanics, thermal expansion coefficient and minimum thermal conductivity. This shows the potential of tungsten/graphene/tungsten composites in radiation resistance.