The erosion mechanism and deformation characteristics of rhomboid-shaped particle impacting metal beam are studied. Physical experiments of rhomboid-shaped particle impacting cantilever beam and fixed–fixed beam are carried out, respectively. The erosion behavior of particles and deformation characteristics of beam are captured by high-speed imaging system. Meanwhile, the numerical models of rhomboid-shaped particle impacting beam, based on FEM-SPH coupled method, are established. The effects of the geometrical parameters of the beam, the incident conditions of particle and the impact position on the elastic–plastic deformation of beam and rebound behavior of particles are further analyzed. The results show: (1) The width of cantilever beam affects its maximum deflection and deformation; (2) The threshold value of breakdown velocity is controlled by the substrate size; (3) The increment of internal energy is basically independent of the impact position; (4) The deflection value at impact position of beam is maximized under the critical impact condition.

研究了菱形颗粒撞击金属梁的冲蚀机理和变形特性。分别进行了菱形颗粒撞击悬臂梁和固定-固定梁的物理实验。通过高速成像系统捕捉颗粒的侵蚀行为和光束的变形特性。同时，建立了基于FEM-SPH耦合方法的菱形粒子撞击梁的数值模型。进一步分析了梁的几何参数、粒子的入射条件和撞击位置对梁的弹塑性变形和粒子的回弹行为的影响。结果表明：（1）悬臂梁的宽度影响其最大挠度和变形；(2)击穿速度阈值受基板尺寸控制；(3)内能的增量基本与撞击位置无关；(4) 在临界冲击条件下，梁冲击位置的挠度值最大。