Analysis And Research On Inner Hole Polishing Process Based On Abrasive Flow Technology

Parts with intricate pore structures are extensively applied to aviation,optoelectronics,computer,mold manufacturing,and other areas.In order to guarantee the operating performance and service life of pore type components,improving the quality of the inner surface of parts is a critical technical problem.Traditional machining methods have limitations in polishing,chamfering,and deburring the surface and interior of parts.Therefore,a new type of special machining technology,abrasive flow polishing,is proposed for precision machining of polished channel parts.In order to deal with the issue of complicated internal structures in hydraulic valve block holes and curved holes produced by additive manufacturing,which are difficult to perform precision machining.In order to carry out the machining process,this article proposes to use solid liquid twophase abrasive flow precision polishing technology.Numerical simulation is used to study the effects of inlet pressure,abrasive concentration,abrasive particle size,and other variables on the abrasive flow machining effect using the fluid simulation program FLUENT.The velocity,turbulent kinetic energy,static pressure,and wall shear force of the abrasive flow in the inner channel under different inlet pressures,particle size,and abrasive concentration were simulated.Hydraulic valve blocks were selected as experimental objects to verify the numerical simulation results when the inlet pressure was 8 MPa,the abrasive concentration was 0.10,and the abrasive particle size was 200 mesh;Then,an additive manufacturing bend was selected as an experimental sample,and three processing factors-inlet pressure,abrasive particle size,and abrasive concentration were investigated by orthogonal tests,on the polishing quality of the inner surface of the bend before and after the abrasive flow polishing additive manufacturing bend.The tests found that the order of the effects of three processing factors on the inner surface roughness of the bend after the abrasive flow polishing additive manufacturing bend was from strong to weak:inlet pressure,abrasive concentration,and abrasive particle size.A combination of polishing parameters of P=6MPa,0.20 abrasive concentration,and 400 mesh abrasive particle size has been found to be optimal,resulting in a marked enhancement of the inner surface’s processing quality.The numerical simulation and experimental study of abrasive flow polishing of internal channels in porous parts provide a theoretical basis for the further development of polishing technology for complex components with pore structures.