电推进羽流粒子束溅射的蒙特卡罗模拟

Monte Carlo Simulation of Electric Propulsion Plume Particle Beam Sputtering

为了研究电推进羽流对推力器及航天器造成的溅射腐蚀作用,采用蒙特卡罗方法对羽流等离子体对材料的溅射进行模拟,研究了溅射的级联碰撞机理,并开展了Xe离子正入射、斜入射Cu材料的溅射率、溅射产物的能量分布以及空间角分布的研究。结果显示,蒙特卡罗方法对溅射率和能量分布的计算结果与试验结果吻合较好,误差<30%,但是斜入射溅射率和方向分布吻合较差,最大误差>50%。认为影响溅射的主要因素为晶体的结构、二体碰撞的基本假设以及入射粒子的注入累积效应。

To study the sputtering effects of the thrusters and spacecraft caused by electric propulsion plume,the Monte Carlo(MC)method is used to simulate the sputtering of materials by plume plasma. The cascade collision mechanism of sputtering was studied.The sputtering rates of Cu materials under normal and oblique incidence of Xe ions were investigated,and the sputtering rate,the energy distribution and the angle distribution of the sputtering products were studied. The results show that the calculation results of sputtering rate and energy distribution by MC method are in good agreement with the experimental results,but the oblique incidence sputtering rate and the angle distribution are in poor agreement. It is considered that the main factors affecting sputtering are crystal structure,the basic assumption of two body collision and the injection accumulation effect of incident particles.