Numerical Simulation Of Transient Multiphase Field During Hybrid Plasma-laser Deposition Manufacturing

摘要

The hybrid plasma-laser deposition manufacturing (PLDM) process is developed based on the plasma deposition manufacturing (PDM) technology. PLDM belongs to the three-dimensional (3D) welding technology and involves the laser power as an augmented heat resource. Compared to PDM technology, the PLDM process has many advantages such as a higher power density, higher processing precision, refined microstructure, and improved mechanical performance of forming components. There exist complicated physical and metallurgical interaction mechanisms due to the combination of PLDM along with the rapid melting and solidification process. Moreover, the interaction between the laser and plasma arc also directly influences the forming quality and precision of the 3D metal components. Therefore, the proposed work is a preliminary attempt to study the transport phenomena in the PLDM process, in which the heat transfer, fluid flow, and molten powder depositing processes have been investigated in detail. The numerical study is performed by using a pressure-based finite volume difference technique after making appropriate modifications of the algorithm. The associated solid/liquid phase transformation process is involved by using an enthalpy-porosity method, and the level-set approach is introduced to track the evolution of weld surface of the deposition layer with powder feeding. An experimentally based hybrid heat input model is developed to involve the influence of the interaction of laser and arc plasma on the redistributed energy absorption by the material. Corresponding experiments of the PLDM process are performed using the same parameters as in the computations, showing a good qualitative agreement.