Study On Electron Beam Cladding NiCoCrAlY Molten Pool Of Inconel617 Nickel-based Superalloy

Inconel617 nickel-based super alloy has good instantaneous and long-term mechanical properties at high temperatures.Its high oxidation resistance and high carbonization resistance are widely used in aerospace and other industrial fields.Since most of the failures of metal material properties in applications start from the surface,electron beam cladding surface treatment technology is one of the effective ways to improve the surface quality of alloys.NiCoCrAlY can improve the surface oxidation resistance of the material.However,due to the relatively concentrated energy in the electron beam cladding process,a molten pool is formed on the surface of the alloy and a large temperature gradient and overmelting phenomenon are generated,which affects the mechanical properties of the material.Therefore,an in-depth study of the temperature field and the molten pool can improve the understanding of the law between electron beam cladding and process parameters.This paper selects Inconel617 alloy as the matrix and NiCoCrAlY alloy powder as the cladding layer to prepare the corresponding experimental materials.Based on the finite element analysis software ANSYS and fluent,the temperature field and molten pool model in the electron beam cladding process are established.Through APDL and UDF to compile relevant programs,analyze the process parameters the influence of electron beam current,beam spot diameter and scanning speed on the temperature field and molten pool and the change law.The simulation results show that the peak temperature field of the cladding layer is approximately positively correlated with the electron beam current;the greater the scanning speed of the electron beam,the lower the temperature field peak into a negative correlation;the larger the electron beam spot diameter,the smaller the temperature field peak negative correlation.The temperature field in the cladding process is divided into three stages,rapid heating,stable stage and cooling solidification stage.During the electron beam cladding process,the cladding layer melts and the matrix is micro-melted to form a molten pool metallurgical bond.The relationship between the molten pool penetration and the process parameters is analyzed by fluent simulation.The simulation results show that the penetration width of the molten pool and the electron beam current are approximately positively correlated;the greater the scanning speed of the electron beam,the penetration of the molten pool formed by the cladding layer and the substrate decreases in a negative correlation;the electron beam spot The larger the diameter is,the melt width of the molten pool formed by the cladding layer and the matrix decreases in a negative correlation.Along the thickness direction of the specimen,the molten pool becomes smaller as it goes downwards,and the molten pool formed by the cladding layer and the matrix conforms to the elliptical division of the Gaussian heat source.Combined with the simulation results of the temperature field,comprehensively obtained the ideal electron beam Inconel617 surface cladding NiCoCrAlY process parameters: I=20m A,D=4mm,v=8mm/s.Analyze the simulation results of the temperature field and the molten pool,obtain the optimal process parameters,and use the SEBW60-6P electron beam processing equipment to carry out the electron beam cladding experiment.The experimental results and the numerical simulation results are compared and analyzed.Observed by SEM,the shape of the molten pool conforms to the elliptical distribution of Gaussian heat source.The width of the molten pool is 4.3mm and the penetration depth is 1.7mm.Utilization of the method of finite element simulation of the relationship between process parameters and the electron beam penetration weld width,obtained puddle width 4.5mm,1.75 mm deep melt,simulation results and the actual results of a similar experiment,the model proved to be reasonable And reliability.This study provides a certain reference basis for further research on the relationship between the electron beam cladding bath and the process parameters,and has certain guiding significance.