Study On Surface Residual Stress Of High Temperature Superalloy GH4169 During High Speed Cutting

As the most representative superalloy material, Nickel-based high temperature alloy GH4169 was widely used in the aerospace field because of its good resistance to fatigue, creep, oxidation and corrosion. However nickel-based superalloy is a typically difficult to machining material with high cutting force, high cutting temperature, and serious tool wear problems in the process of machining. High-speed machining now become one of the main ways to resolve Nickel-base superalloy and difficult materials machining due to its advantages.The machined surface residual stress easily lead to deformation and surface crack, impact of the workpiece surface quality, thereby affect the mechanical properties and the fatigue life of the workpiece.Therefore, in this paper, GH4169 has been just chosen to study, using the finite element and experiment methods to study the distribution of its high-speed machining surface residual stress.Firstly, the cutting process of high-speed cutting GH4169 has been simulated by finite element software ABAQUS. The formation process of the serrated chip and the machined surface residual stress have been simulated. The effect of cutting parameters and tool geometry parameters for the size and distribution of surface residual stress were analyzed with single factor method.Secondly, the three-dimensional finite element model of milling was established, by applying the orthogonal experimental method and choosing three factors and four levels orthogonal table on the high-speed milling of GH4169, to study the influencing rules of milling speed, cutting depth and feed rate per tooth on the surface residual stress. Range and variance analysis were utilized to get the significant influencing factors on residual stress. Results show that: higher milling speed, smaller cutting depth and feed rate per tooth can get better surface residual stress state.Finally, the high-speed milling experiments were carried out on GH4169 and the hole drilling method was used to measure workpiece surface residual stress. Compared with the simulation results, by analyzing the causes of errors in the simulation and experimental results to verify the accuracy of the finite element simulation model.