Simulation And Optimization Of The Process Scheme For Rotary-Type Mass Finishing Of Blisk

As the core part of aeroengine,the surface quality and profile accuracy of blisk have a great influence on the aerodynamic performance and service performance of the whole engine.After milling,the surface quality of blisk is poor,and micro cracks will be formed on the blade surface,so the blade surface must be polished.Mass finishing is a kind of free abrasive finishing technology,which is used to improve the surface quality and integrity of parts.Among them,the rotary-type mass finishing has the advantages of good machining uniformity and large size range of workpieces,which is suitable for the surface finishing of special-shaped parts,and can be considered as the polishing processing scheme of the blisk.Based on the discrete element method and the Archard wear model,the simulation calculation and data analysis are carried out for the rotary-type mass finishing of the blisk,and the optimal design scheme is proposed,which provides a reference for the practical machining application and lays a theoretical foundation.The main research contents are as follows:(1)The preprocessing work of EDEM simulation software based on discrete element method is studied,and the relevant parameters are set according to the requirements of the blisk mass finishing.Hertz-Mindlin with Archard Wear contact model is selected between particles and workpieces in the processing,and the Archard wear and cumulative contact energy of blade profile are calculated and counted.Solid Works software is used to complete the blisk modeling,and ANSYS software is used to complete the mesh division of the model.Contact parameters required for simulation and simulation process are set according to the actual machining requirements.A new data extraction method for complex surfaces is proposed,and relative standard deviation is introduced as the evaluation standard of processing uniformity.(2)In order to verify the accuracy of the simulation calculation based on the discrete element method and the Archard wear model,the BJG-LL05 automatic free abrasive finishing equipment is selected to finish the TC4 titanium alloy test piece with the same material as the blisk,and the simulation experiment of the same model and parameter setting is completed.The experimental results and simulation results are compared.Through the comparative analysis of the change value of the surface roughness in the experiment and the wear amount in the simulation,it is found that the overall trend of the simulation results under different parameters is consistent with the experimental results,thus verifying the authenticity and accuracy of the simulation calculation of the mass finishing process based on the discrete element method and the Archard wear model.(3)The simulation experiment is carried out for the horizontal rotary-type mass finishing of the blisk.The effects of the abrasive loading quantity and the barrel speed on the processing effect are studied.The results show that the processing efficiency of the blade profile is greatly affected by process parameters,and the convex and the concave show obvious differences.The rotary-type mass finishing can effectively ensure the uniformity of processing between different blades,and under the condition of 50%loading quantity and 70 rpm,the processing uniformity of different areas of the same blade profile is the best.Considering the processing efficiency and the processing uniformity,the following parameter ranges are preferred:50%?60%loading quantity;0.8n_max?0.95n_max speed.(4)In order to improve the processing efficiency and uniformity of the horizontal rotary-type mass finishing of the blisk,three optimization design schemes are put forward and the machining process is simulated.According to the comparative analysis of the simulation results,it can be concluded that:the two-way rotation can improve the contact form difference between the convex and the concave in the machining process,but it is still difficult to solve the problem of uniformity processing at different positions of the blade surface.The processing efficiency of blade surface can be improved when the tilt angle is lower than 15degrees,but the processing uniformity of different positions of the same blade surface has not been improved significantly.The vibration-rotation composite mass finishing can not only ensure the processing uniformity among different blades,but also greatly improve the processing efficiency of the blade surface,and effectively improve the processing uniformity on the same blade surface This optimization design should be considered as an indispensable machining form in the practical application of the blisk mass finishing.