Research On Flow Field Simulation And Polishing Process Of Titanium Alloy By Immersion Air Jet Polishing

Titanium alloy is an extremely widely used metal material at present.It is often used in cutting-edge medical treatment,oil exploration,aerospace and other fields.Therefore,it has extremely high requirements for the performance of titanium alloy.Compared with other traditional polishing techniques,immersion air jet polishing has the characteristics of high flexibility,strong adaptability and high polishing accuracy,and can also complete precision polishing for parts with complex structures.In this paper,an experimental platform of immersion air jet polishing system is established.Secondly,based on the Fluent software and combined with the fluid mechanics theory,the internal flow field of the immersion air jet was simulated.The surface pressure distribution and the velocity distribution near the wall surface were obtained.Based on the control variable method,the evolution law of the flow field under different parameters was studied.Then,based on the micro-cutting model of plastic materials,the erosion removal mechanism of immersion air jet machining titanium alloy materials was studied,and the polishing erosion mechanism under different abrasive parameters was explored from the perspective of microscopic evolution.Finally,starting from the analysis of polishing experiments,the influence of processing parameters on the surface quality in immersion air jet polishing was explored,and a roughness prediction model of titanium alloys was established.The specific content of this article is as follows:(1)A immersion air jet polishing experimental platform is established,which mainly includes mechanical system,pressure system,control system,etc.In addition,according to the selection of abrasive and the ratio of abrasive liquid in the polishing experiment,a polishing liquid with good polishing performance was configured,and the effectiveness of the immersion air jet polishing device in polishing titanium alloy was verified by experiments.(2)With the help of computational fluid dynamics simulation software,the flow field in the polishing area can be better initially analyzed,and the four factors of injection pressure,injection angle,injection distance and abrasive mass fraction on the pressure of the immersion air jet can be analyzed to the pressure field and the velocity field.(3)Based on the relevant theories of indentation fracture mechanics and micro-cutting,combined with the microstructure photos of the workpiece surface,a model for removing convex peaks on the surface of single particle erosion is established,and the block,spherical and other irregular abrasive particles in the same and different directions are analyzed.The impact failure form of plastic materials was studied,and the influence law of size,shape and impact angle on surface polishing was studied.(4)Through single factor experiment,study the influence of processing parameters such as injection pressure,injection distance,injection angle and polishing liquid formula on polishing quality.Then through orthogonal experiment and range variance analysis,explored the optimal level corresponding to surface roughness.The combination and primary and secondary influencing factors were used to optimize the processing technology of immersion air jet processing of titanium alloy materials.Finally,the roughness after polishing was predicted by establishing a multiple linear regression model of immersion air jet polishing of titanium alloys.