Research On The Thermal Coupling Mechanism Of Metal Powder Feeding Additive Manufacturing Based On Digital Twin

With the development and progress of science and technology,additive manufacturing technology has gradually become a new direction in the field of manufacturing because of its advantages of reusable materials and personalized customization.However,the continuous development of additive manufacturing technology always faces some technical bottlenecks(such as: Poor process repeatability,high production cost,easy to appear in the processing of pore cracks,etc.),so that the quality of the molded parts cannot be guaranteed.The trial-and-error experiment in the process of exploring process parameters leads to high processing cost and other problems have always restricted the development of additive manufacturing technology,and it is impossible to realize the real-time feedback control and optimization of process parameters.Making it difficult to further develop in aerospace,biomedical and other precision manufacturing industries.Therefore,in order to solve the above problems,this paper proposes to construct a digital model of power-feeding metal additive manufacturing process mechanism based on digital twin technology,so as to realize the prediction of molten pool temperature field and residual thermal stress,and finally achieve the purpose of real-time feedback and optimization of process parameters.In order to accomplish the above goals,this paper first uses Ansys finite element analysis software,uses 316 L stainless steel as raw material and uses laser beam as heat source to establish thermal coupling simulation analysis model of powder feeding metal additive manufacturing process,and explores the specific distribution of molten pool temperature field and residual thermal stress in two cases of single-layer multi-channel and multi-layer single-channel,and then through specific experiments,The temperature field data of the molten pool collected in the process of metal powder feeding additive manufacturing is compared with the simulation results,so as to verify the accuracy of the simulation results.Secondly,the regression model of laser power,scanning speed and substrate preheating temperature is established by regression design and analysis method,and its influence on the melting pool temperature and residual thermal stress in the metal powder feeding additive manufacturing process is analyzed.Finally,the data model constructed by regression analysis was used to establish the digital twin for the powder feeding metal additive manufacturing process,taking the melting pool temperature of metal powder feeding additive manufacturing as the input excitation data and the residual thermal stress as the output data.The twin models were established for the laser power and scanning speed as the main design parameters.The residual thermal stress obtained by digital twin technology is compared with the finite element simulation results.The results show that the overall distribution trend is basically consistent.However,the calculation time required for the prediction results by digital twin is much less than that consumed by finite element analysis,so the real-time feedback and optimization of process parameters can be realized,and the printing efficiency can be greatly improved.。...