| In the field of Aeroengine,the precision finishing of a large number of parts with complex surface structure has always been the hotspots and difficulties of research.The blisk is a typical representative of aviation disk parts,after electrolysis machining and electrochemical machining,although the surface roughness of the inner flow channel can be effectively reduced,but it still faces problems such as long processing time,low efficiency,and exist the recast layer on the processed surface.Abrasive flow machining technology has a high accessibility,it can polish a variety of complex parts,and show a broad application prospect in the field of precision finishing of aviation parts.The paper focus on the research of the AFM technology on blisk,the main work and achievements are as follows:(1)A single-factor experiment was conducted for nickel-based superalloy samples,and the surface integrity was studied from four dimensions: surface roughness,Vickers hardness,surface morphology,and residual stress.The effects of abrasive particle size,processing pressure,and abrasive dosage on processing were analyzed.It has been found that when using the same abrasive to process,the rate of roughness reduction continues to decrease.It is found that the processing quality is positively related to the processing pressure and the dosage of abrasive,but when the upper limit of processing quality is reached,it has no significant effect to increase the pressure and the amount of abrasive.It was found that AFM can effectively remove the surface recast layer,and convert the surface residual tensile stress into compressive stress at the same time,which significantly improves the fatigue strength.(2)A special fixture was designed for the AFM on the flow of the blisk,and its structural reliability was verified by static simulation.By establishing the flow channel model with or without the gland and the core mold structure,the fluid simulation was performed,and the distribution of pressure,velocity,and wall shear force in the flow field of the two structures was analyzed.It is proved by the fluid simulation and the experiment that the machining uniformity can be effectively improved and the problem of the abrasive erosion the sharp edges was avoided after adding the gland and the core mold structure.Then the simulation of the machining process under different machining pressure conditions was carried out,it is found that the lager the machining pressure,the higher the processing efficiency,but the worser the machining uniformity.Therefore,the selection of the processing pressure must be balanced between the processing efficiency and processing quality.(3)The research on the processing technology of AFM on the flow of the blisk is carried out.Firstly,it is found that the designed fixture can achieve the designed goal through the pre-experimental research,and the single-factor experiment and the fluid simulation results was summarized,the suitable index for orthogonal experiment is selected.The orthogonal test shows that the best processing effect can be obtained when the abrasive mesh number is 36 and 80 mixed,the machining pressure is 11 MPa,and the cycle number is 20.At the same time,the conclusion of which particle size abrasive is suitable for the machining surface with different initial roughness ranges is obtained.Through the research in this article,it provides valuable experience for the application of abrasive flow technology in the precision finishing of aerospace complex parts. |
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