The Analysis And Experimental Study On The Flow Field Of Strong Constraint Abrasive Jet Polishing

With the development of optics and electronic information technology,the optics glass which used as optoelectronic base materials is becoming indispensable optics element in the industry area of national defense,aerospace,and energy.And with the continuous improvement of science and technology,people propose high requirements to the surface quality of optics glass.But traditional processing method is difficult to reach all the requirements,especially for complex curved surface polishing.Facing the processing requirement of hard and brittle materials complex curved surface with high precision and low damage of optics surface,for the problem of jet beam divergence and impact damage in the process of abrasive jet polishing,a processing method of strong constraint abrasive jet polishing was proposed.In order to verify the feasibility and validity of this method,firstly,we make the fluid domain model of the inside of polishing tool head and jet flow field,and make the figure simulation to the whole fluid model and analysis the flow characteristics of different polishing gap.By comparing and analyzing,we can get the result that 0.5mm polishing gap is the best polishing gap.Then we use the transparent polishing head to do the particle image velocity measure experiment,and make the observation and analysis to the flow field inside of nozzle.From comparing and analyzing the results,we can draw the conclusion that with the gradually decreased of polishing gap,particle inside of free fluid of the processing area moves more severe,and produces more swirl,which can better make the polishing processing to the component.Moreover,when the polishing gap is 0.5mm,flow field is uniform,which is equal to simulation result.At last,make the orthogonal experiment to all kinds of influential factors of strong constraint abrasive jet polishing technology of hard brittle materials parts complex curved surface low damage and high precision polishing to analysis the actual impact on processing effect of polishing gap,abrasive granularity and additive concentration.The experimental results show that the particles have obvious cutting effect to the processing wall,the processing method of strong constraint abrasive flow can effectively improve the surface quality of the workpiece and make its surface tends to be smooth.The whole experiment also strongly proved that strong constraint abrasive flow has effectiveness and feasibility to the hard and brittle material processing.By comparing,we know that the most suitable polishing parameters is 0.5mm polishing gap,1500# abrasive and 0.1% of the additive concentration.It verifies the correctness of the simulation and observation experiment results.The strong constraint abrasive jet polishing method is one kind of abrasive flow polishing,it has its unique advantages when make the process to the hard and brittle materials.The designing polishing device will change the loose abrasive particle jet to jet processing method to compulsory constraints abrasive jet cutting processing way,solving the problem of jet beam divergence in the processing of abrasive jet,reducing normal shock waves of abrasive to the workpiece’s surface.Based on the jet technology research present situation in different fields and according to different materials,we can make the research of materials removal mechanism to a variety of hard and brittle materials which are difficult to process.