Numerical Simulation Effect Of The Laser Assisted Temprature On Particle Deposition

The supersonic laser deposition (SLD) is a new fabrication process which combines the supersonic powder stream found in cold spray with laser heating the deposition zone. In the spraying process, the change of any process parameters will have an important influence on obtaining coating. Therefore, the study of the optimal parameters for making good spraying process is important. In the paper, the process of single particle impact under the heating deposition zone is simulated using the finite element method (FEM). The appropriate spraying process parameters are determined under that the simulation result is compared with experiment, which is favorable for guiding SLD process.Because of the characteristics of particle high-speed impact on substrate instantaneity, the deformation behaviors and the adhesion behaviors of the particle and substrate cannot be observed directly. So, the software ANSYS Multiphysics/LS-DYNA has been developed to analyze particle impact process intuitively and vividly. The heat conduction, the stress, the strain and the deposition effect of the particle and substrate under the different heated temperature are discussed. And the effect of the particle size for getting the spray is investigated by altering the particle diameter. In addition, the SLD experiment is served for verifying the reliability of the numerical simulation.The conclusions can be obtained as followed:(1) The extent of the deformation behaviors of particle and substrate, the depth of the deposition zone and the thickness of the layer increase with the heated temperature of deposition zone increasing.(2) The metal jet phenomenon and the adiabatic shear instability phenomena have not been appeared during the particle impact. In addition, no oxide and no new material generation are in obtaining layer. The element of the layer and the powder is similar nearly.(3) The optimal spraying process parameters:the work gas of N2 at pressure of 30 bar and temperature of 450 ℃, the speed of 15 mm/s, particle diameter of 35 um, deposition temperature of 1000 ℃,1100 ℃.