Simulation Of Supersonic Particle Bombardment Magnesium Alloy For Surface Nanocrystallization

With the rapid development and wide application of numerical simulation, using numerical simulation to optimize the design of experiment has become a simple, speedy and cost-effective means in optimizing process. Moreover, to many invisible experiment processes, the use of computer simulation can achieve visualization, make it easier to understand the experiment phenomenon, and to get a more accurate analysis.In this paper, fluid simulation software has been used to simulate the production of the supersonic airflow, as well as the acceleration of particles. Supersonic combustion flow was produced by the oxygen and fuel oil combustion explosion. A limited general rate combustion model, the EDC reaction rate model, RNGκ-εturbulence model and DO radiation model have been used for the supersonic airflow in this paper. The gas-solid two-phase flow model was used in the process of particles speeding up, and the particles were tracked by Lagrange method. Through the simulation of airflow and particle velocity field, temperature field and pressure field, it has been confirmed that the velocity of gas and particles have reached supersonic speed.Finite element analysis software has also been used in this paper to simulate the process of fine particles bombardment the magnesium alloy samples. The simulation is mainly based on the momentum equation, the quality equation, energy equation, boundary conditions and material constitutive equations. The impact of particle velocity and diameter to the surface plastic deformation of the magnesium specimen has been researched. Simulation results showed that the higher of the particle velocity and the larger diameter can form more obvious surface plastic deformation. The performance of the nanocrystalline has been deduced through the comparison between the simulation results and the experiment results.