Simulation Study On Vibration And Processing Optimization In Abrasive Belt Grinding For Blisk

Blisk is a key part of modern aero-engine,and its surface processing quality affects the performance of aero-engine directly.Because the blisk has characteristics of easy deformation of the thin-walled blade,narrow inter-blade channel,free surface of the blade and the difficult processing of the material,the precision machining of blisk has been a difficult problem in the field of aviation manufacturing.The combination of the new open belt grinding technology and the multi-axis CNC machine tool is a relatively ideal blisk grinding solution.However,due to the structure characteristics of blisk and the characteristics of the new open belt grinding technology,the grinding system formed a unique triple weak rigidity grinding conditions which composed of the thin-walled blades,slender braket arm and flexible contact wheel,thus causing different degrees of vibration during the grinding process,which impacts the dimensional accuracy and surface quality of blisk-blade surface seriously.For the problems above,this paper studied vibration law of blisk belt grinding by the means of theoretical modeling and numerical simulation.The theoretical grinding stability conditions and the optimal combination of process parameters are obtained.The main research work of the project completed as follows:(1)From the perspective of Blisk structure,grinding equipment and grinding methods,the causes of the triple weak rigidity in the blisk-blade surface grinding is analyzed,and the static stiffness of the grinding system during grinding is obtained by static analysis.(2)Based on the numerical simulation method,the static and dynamic characteristics of the key structural parts of the grinding system are analyzed.By static analysis and contact analysis,the deformation and stress distribution of the structure under the grinding pressure are obtained.By modal analysis,the natural vibration characteristics of the structure are obtained.By harmonic response analysis,the steady state response of the structure under the excitation force is obtained.(3)Based on the physical model of the grinding system and the grinding force of abrasive belt grinding,the mathematic model of the grinding chatter of the blisk-blade surface grinding belt is established.Then,the stable grinding conditions and the structure and process factors influencing the grinding vibration are obtained through theoretical analysis.(4)Based on ABAQUS,the finite element model of abrasive belt grinding for the blisk-blade surface under weakly rigid condition was established.The process parameters influencing grinding stability were simulated by orthogonal test.Then,the optimal combination of grinding parameters is obtained by evaluating the indicators.Finally,the feasibility of the grinding parameters is verified by experiments.