Research on sputtering behavior of three beams coaxial laser cladding powder based on the interaction of lasers and powder

Abstract

During laser cladding, a mutual coupling effect exists among the powder, carrier gas, shielding gas, and laser beam. The key to optimizing the cladding process is determining the effective utilization of the powder and revealing the interaction mechanism of the laser and the powder. In this paper, a continuous-discrete phase coupling model of the interaction between 316L powder, carrier gas, and protective gas in laser cladding is established, which is based on a three-beam coaxial powder feeder. Quantitatively reveals the influence of working distance, carrier gas flow rate, and shielding gas flow rate on the state of powder aggregation and the external flow field of the powder nozzle during the cladding process. To improve the utilization rate of the powder, the cladding process parameters were optimized by the orthogonal test method. A custom program of laser heat source function was written to calculate the temperature rise of powder under the interaction of the laser and the powder. The relationship between powder temperature and cladding process parameters was established. The powder aggregation shape obtained by the numerical simulation was compared with the actual aggregation shape. The temperature of the powder particles at a fixed position was collected by a noncontact infrared thermometer DT-8856H and compared with the simulation results to verify the validity of the established model. The research in this paper can effectively reveal the powder participation and the interaction mechanism of the laser and the powder during laser cladding. It can provide a theoretical basis for optimizing the cladding process parameters throughout the cycle and improving the quality of the cladding layer.