Research On Cutting Edge Passivation To Turning GH4169 Surface Integrity

In the field of superalloys,nickel-based superalloys have an extremely important position.They are widely used in the hottest parts of aerospace engines and industrial gas turbines.Nickel-based superalloys have high fatigue oxidation and corrosion resistance.At the same time,due to the low thermal conductivity of the nickel-based superalloy,the machining difficulty is greatly increased.During the cutting process of the tool,the surface plastic deformation of the superalloy is severe,resulting in machining surface quality problems such as work hardening and residual stress.In view of the above problems,this paper studies the influence of the cutting edge passivation radius of GH4169 on the surface integrity of the finish.By referring to literature surveys,test experiments,theoretical analysis and other means,the surface roughness,metamorphic layer,residual stress,Work hardening and other research phenomena to analyze the influence of the blade passivation radius on the surface integrity of the superalloy,which has a great reference value for the improvement of the processing quality of the superalloy,the microstructure design of the tool,and the improvement of the cutting performance of the tool.The specific work is as follows:First of all,by referring to the literature and research,the cutting edge passivation radius parameters of the blade models of nickel-based superalloys for precision machining by excellent tool manufacturers at home and abroad were measured,and the cutting edge passivation radius of the cutting-edge nickel-based superalloys was obtained.The main parameters range from 0.01 to 0.05 mm.And through the existing passivation process,different passivation process and blade passivation radius of the blade were prepared,and the blade micro-geometric parameters were analyzed.Secondly,the cutting GH4169 experiment was carried out on the prepared blade,the effects of different passivation processes and cutting parameters on the surface roughness and residual stress of the cutting GH4169 were analyzed,and a comprehensive passivation process was selected for sandblast passivation.The preferred processing parameters within the selected range of finishing nickel-based superalloys are: Vc=60?70m/min,fn=0.02?0.075mm/r,ap=0.35?0.75 mm,r=0.02?0.04mm?Thirdly,the two-dimensional cutting force model after cutting edge passivation was established,and the cutting force test was conducted.As the cutting edge passivation radius increased,the main cutting force also increased.The tool wear failure of blades with different passivation radii was observed.With the increase of the passivation radius,the wear rate of the tool increases,and the appropriate passivation radius of the cutting edge of the tool can reduce the groove wear of the flank of the tool and increase the life of the tool.Finally,the surface integrity(surface roughness and surface morphology,white layer and metamorphic layer,work hardening,residual stress)of cutting GH4169 under different cutting edge passivation radius within the range of preferred finishing parameters are systematically analyzed.