钨晶界中氦和氢性质的分子静力学模拟

发布时间：2018-05-24 06:00

  本文选题：氦 + 氢　； 参考：《广西大学学报(自然科学版)》2017年06期

【摘要】：国际热核聚变实验堆(ITER)中的偏滤器部分受到大量氦、氢离子流轰击,钨因熔点高、高温性能优异而常被选作这一部件的护甲材料,但氦、氢倾向于在晶界等缺陷处聚集成团簇,从而引起钨表面起泡、肿胀等,致使材料性能下降,使用寿命下降。文中采用分子静力学方法研究了氦和氢在钨晶界附近的性质。首先计算了25个绕100轴旋转不同角度的对称倾斜钨晶界的晶界能,选取其中能量较低的∑5(310)和∑5(210)晶界为研究对象,计算了缺陷与晶界的相互作用。结果表明:在晶界附近,垂直于界面的方向上原子层间距明显增大,晶界的膨胀畸变和面间滑移为缺陷提供了有利环境;晶界的影响区域为4姒,在这一范围内空位、间隙氦和间隙氢的形成能小于块体中的;当离晶界面距离大于4姒,可近似认为是块体。研究结果可为钨中氦/氢泡生长和释放相关的实验提供一定依据和指导。
[Abstract]:Part of the divertor in ITER is bombarded by a large amount of helium, hydrogen ion current, tungsten is often chosen as the armor material of this part because of its high melting point and excellent high temperature performance. However, helium and hydrogen tend to gather into clusters at defects such as grain boundaries. As a result, tungsten surface foaming, swelling and so on, resulting in a decline in material properties and service life. The properties of helium and hydrogen near tungsten grain boundaries have been studied by molecular statics. Firstly, the grain boundary energies of 25 symmetrical inclined tungsten boundaries with different angles rotating around the 100 axis are calculated. The lower energy 鈭，

本文编号：1927948