Design Of Powder Delivery System For Fgm Additive Manufacturing And Simulation Of Forming Process

With the rapid development of science and technology,especially in the military field and aerospace field,the material properties and process performance requirements of products are becoming more and more strict,and the mechanical properties and functional adaptability of common single materials and composite materials are difficult to meet the needs of special environmental conditions,therefore it is urgent to develop a new type of Functionally Graded Material(FGM).In the preparation of FGMS,the classical method shows obvious deficiencies in terms of efficiency and precision.The method has gradually shifted from the traditional special processing methods to the rapid prototyping manufacturing technology,and the additive manufacturing technology for FGMS has gradually become the mainstream technology.As an important part of laser additive manufacturing forming equipment,the powder feeding system is also facing more severe challenges in the process of additive manufacturing of FGMS.It is of practical significance to design and develop a powder feeding system for FGMS.In this paper,mainly designing the powder feeding system for FGM additive manufacturing and simulating the forming process.According to the specific powder feeding requirements in the preparation process of FGMS,design the mechanical mechanism of the powder feeding system in detail.Optimizing the mechanical structure parameters of the powder feeding system through the simulation analysis of powder concentration in the powder feeding process.The transform situation of temperature field and stress-strain field in the forming process provides a theoretical basis for the improvement and optimization of forming process parameters and forming product performance.The main research contents are as follows:(1)Based on the analysis of the requirements of various fields of FGMS and the superiority analysis of laser additive manufacturing technology in the preparation of FGMS,constructing the overall design scheme for the mechanical structure of the powder feeding system.For the functional requirements of the powder feeding system of the FGM forming process,comparing the principle of each device and the deficiency of existing equipment,designing each mechanical component in detail.(2)Simulation study on the powder concentration process of FGM powder feeding system.Based on the gas-solid two-phase flow principle of FLUENT fluid dynamics,simulating and calculating the gradient change of mixed powder under different powder delivery modes and different channel inclination angles.Optimizing the designed Powder spray of powder feeding system through the calculation results.,and verify the superiority of the whole system.(3)Simulation study of the temperature field during the forming process of FGMS.Through the finite element simulation technology,simulate the two kinds of forming methods of FGM single channel multi-layer cladding forming and single layer multi-channel lap cladding forming,and study the temperature field change of the formed parts.By analyzing the influence of forming process parameters on the temperature field,optimize the forming process.(4)Based on the simulation results of the above temperature field,simulating the stress and strain fields in the process of FGM.Through the analysis of the stress and strain at the key points,analyzing the influence of the forming process parameters on the properties of the formed parts,determine the deformation and crack causes of the FGM forming parts and the control methods to improve the performance of the formed products.