Basic Research Of The Simulation Of Laser-plasma Interaction

The hybrid plasma-laser deposition manufacturing (PLDM), which uses hybrid plasma-laser as thermal resource, is one type of rapid manufacturing technology. It uses metal powder directly to rapidly fabricate parts and solves the problems of long manufacturing cycle and high costs. However, compared with the technology adopting single laser as thermal resource, the width of deposition layer augment, and metal power were wasted when the thin wall parts were deposited. We expected that the plasma arc beam could be compressed in order to economize metal power and be more suitable for processing thin wall parts when the laser was introduced. Accordingly in this paper the constringent degree of plasma arc beam was simulated and the influencing orderliness were analyzed to provide the scientific evidence for choosing laser parameters logical.The 2D mathematical model for the interaction of ultra-intense laser and over-dense plasmas was established, presenting the spatial position of particles (in other words, the diversification of plasma appearance)and distributing of particles'velocity, simulating the appearance of laser pulse, kinetic energy and electric current intensity of particles. The Maxwell equation was adopted to sue for electric field intensity and magnetic field intensity, then coupling them in Lorenz equation and electric current continuity equation for driving particles and electromagnetic.After the typical physical phenomena was simulated and analyzed, the outcomes were proved accurate, we reduced the laser intension and plasma density to simulate the variability of plasma arc beam which interacted with laser. According to the outcomes, we discussed the orderliness of the main laser parameters (include lasers'average power, pulse width and repetition frequency). Original images gaining by CCD and profile of images dealing with home-made software proved that the model was propitious to study the plasma arc beam. The conclusion and prospect, which were provided in the end of the paper, pointed out that this model can extend to three dimensions and consider different condition, such as the plasma secondary ionization, environment and the angle of incidence to simulate more intuitionistic change of plasma arc beam and conclude more useful parameters for directing experiment.