Research On The Polishing Mechanism And Process Of Compound Spiral Abrasive Flow

Surface processing is always the key point and the difficulty of research at home and abroad,due to the influence of the structure,traditional tool contact polishing is difficult to process comprehensivly,and the workpiece will appear different degree of machining damage and processing is not uniform,the polishing quality is difficult to meet the requirements of the actual machining.In order to increase the corrosion resistance and surface hardness,usually,we will need to hard anodic oxidation of aluminum alloy parts.However,part of the workpiece anode oxide film exist different degree of pigmentation defects,it will affect the appearance quality of the product,seriously,even lead to waste products,which requires polishing treatment is carried out on the oxide film.If the extrusion honing and polishing method is carried for this kind of parts,not only the surface rough degree it is difficult to improve,and may will destroy the thin oxide film.Therefore,it is necessary to improve the finishing method of the original,or explore the new methods for finishing the to realize the ultra precision machining of thin oxide film.For the difficult problem of inner surface of tubing polishing processing,the polishing methods of spiral bound abrasive flow is brought forward in this paper.A restricted passage is formed by configuring a restricted module in combination with the inner surface,The polishing machining based on the low-strength low-speed cutting by abrasive grain can realize the processing of inner surface of workpiece.The main work and conclusions are described as follows:(1)based on the basic theory of particle dynamics and abrasive flow,the physical model of spiral constrained abrasive flow was constructed,and the RNG model and mixed model were selected as the turbulence model and multiphase flow model.(2)based on the particle erosion wear theory,simple analysis of the material removal model,to explore the establishment of a single particle impact model and solid particle erosion wear and the particle impact abrasive wear characteristics of theoretical research,and further analysis of the material removal mechanism.(3)based on the RNG turbulence model and the mixed fluid model,the flow field in the flow channel is utilized by FLUENT.Numerical simulation analysis is made.Simulation results show that the when the constraint module still,abrasive flow in the constraint flow passage to the turbulent state,internal flow velocity field,pressure field and turbulent kinetic energy distribution is uniform,which is conducive to the abrasive flow uniform processing,with improvement of the speed of the modular constraints,the inner channel of the flow rate is gradually increased,strengthen the particles on the wall scraping action,effectively improve the abrasive flow machining efficiency.And the effect of the gap between the workpiece and the constraint module is simulated.The results show that the distance between the two is more favorable to the processing efficiency of the abrasive flow,and the processing efficiency is improved.(4)based on the particle image velocimetry(PIV),the aerodynamic characteristics of the spiral groove were studied to obtain the particle velocity field characteristics and vorticity characteristics,using high speed camera to channel particles were observed the motion characteristics of the flow inside the particle,to verify the correctness of the simulation results.(5)based on the flow field simulation and experiment results,building the reasonable spiral bound abrasive flow machining experiment platform,processing experiment results show that when static modular constraints,under abrasive flow micro force cutting action of trace and the surface quality of the workpiece are effectively improved,with the continuous improvement of the constraint module rpm,the original rough workpiece surface gradually tends to smooth,material removal quantity is increasing gradually,module of high speed rotating motion improves the abrasive flow of the whole machining efficiency,machining experiment results demonstrated the effectiveness of spiral constraining abrasive flow polishing method is feasible and efficient.To sum up,this paper simulate on the correlation properties of spiral flow,and reasonably build up the spiral composite abrasive flow machining experiment platform,simulation and experiment basically coincide,and provides the theoretical basis for the further optimization of the machining process parameters.