In this study, experimental and numerical investigations have been done to explore the effect of the particle properties on the erosion behavior of aluminum alloy during the abrasive air jet machining process by using the novel medium-hard amino thermoset plastic (ATP) and conventional super-hard alumina (Al2O3) particles. In the numerical simulation, a novel linear elastic material model with the failure standard was proposed to define the ATP particle and the conventional rigid material model was used to define the Al2O3 particle; and the impact target model was established by using smooth particle hydrodynamics (SPH) interpolant with the moving-least-squares method. Then a multi-particle impact model based on the SPH and finite element coupling method (SPH-FEM) was developed to investigate the particle impact process. It indicates that the SPH-FEM method can be used to simulate the erosion behaviors of aluminum alloy impacted by the medium-hard ATP particle, and the simulation results are fundamentally consistent with the experimental ones. The results demonstrate that the effect of particle hardness on the erosion behavior of the impact target is about 200 times higher than that of compressive air pressure. More significantly, there exists an optimal impact angle where the surface material can be removed by chip formation resulting in the maximum material removal rate and the surface erosion behavior can be accurately predicted by simulation. Furthermore, with the particle hardness increasing, such optimal impact angle would be reduced accordingly.

In this study, experimental and numerical investigations have been done to explore the effect of the particle properties on the erosion behavior of aluminum alloy during the abrasive air jet machining process by using the novel medium-hard amino thermoset plastic (ATP) and conventional super-hard alumina (Al 2 O 3 ) particles. In the numerical simulation, a novel linear elastic material model with the failure standard was proposed to de ne the ATP particle and the conventional rigid material model was used to de ne the Al 2 O 3 particle; and the impact target model was established by using smooth particle hydrodynamics (SPH) interpolant with the moving-least-squares method. Then a multi-particle impact model based on the SPH and nite element coupling method (SPH-FEM) was developed to investigate the particle impact process. It indicates that the SPH-FEM method can be used to simulate the erosion behaviors of aluminum alloy impacted by the medium-hard ATP particle, and the simulation results are fundamentally consistent with the experimental ones. The results demonstrate that the effect of particle hardness on the erosion behavior of the impact target is about 200 times higher than that of compressive air pressure. More signi cantly, there exists an optimal impact angle where the surface material can be removed by chip formation resulting in the maximum material removal rate and the surface erosion behavior can be accurately predicted by simulation. Furthermore, with the particle hardness increasing, such optimal impact angle would be reduced accordingly.