| As a non-traditional finishing process,magnetic abrasive finishing technology has a wide range of applications,good processing performance and other advantages,which plays an important role in improving the physical and mechanical properties of parts,and has been applied to the surface machining of elbow,valve and shaft parts.Compared with the most widely used granular magnetic abrasive tools,viscoelastic magnetic abrasive tools have good surface adaptability and fluidity,can adapt to various complex surfaces,and particles are not easy to splash in the process of processing,so they have a good application prospect.In view of the current research on rheological properties and components of viscoelastic magnetic abrasive tools is not complete,the processing technology is not mature enough,and there are some problems such as abrasive shedding in the processing process,6061-T6 aluminum alloy is selected as the experimental material to carry out relevant processing and test experiments,and the processing mechanism,rheological properties and processing technology of viscoelastic magnetic abrasive are studied and analyzed.The specific research contents are as follows:(1)The main components and functions of viscoelastic magnetic abrasive tools are introduced.The processing principle and material removal mechanism of viscoelastic magnetic abrasive tools are analyzed.By controlling the amount of dibutyl phthalate,the viscoelastic magnetic abrasives with different properties were prepared.The rheological properties of the abrasives were tested and analyzed by rheometer,and the working law of the rheological properties of the abrasives on the processing effect was explored based on the processing experimental data,which provided theoretical guidance for the later Abrasives preparation and matrix selection.(2)Based on Maxwell software,the magnetic field distribution is simulated and analyzed,and the machining parameters such as machining gap and magnetic pole angle are determined.The influence of the main components of the grinding tool on the machining effect was studied by single factor experiment.Under the current experimental conditions,when the particle size is 320 mesh,the mass ratio of two phases to matrix is 1.5,the amount of dibutyl phthalate is 1%,and the amount of dimethylsilicone oil is 2.5%,the best surface processing effect can be achieved.(3)Based on the response surface method,with the amount of dibutyl phthalate added,the amount of dimethylsilicone oil added,the mass ratio of matrix to two phases,and the particle size of abrasive as the response factors,and the surface roughness reduction rate as the response variable,the influence of various factors and their interaction on the surface roughness reduction rate of workpieces was explored.Through the residual and variance analysis of the experimental data,the multiple regression equation about the reduction rate of the roughness of the abrasive ratio is obtained.Through the model optimization,the optimal design of the abrasive ratio scheme is carried out,and the experimental verification is carried out.When the amount of dibutyl phthalate is 0.8%,the amount of dimethylsilicone oil is 2.2%,the abrasive particle size is 380 mesh,and the mass ratio of the matrix and two phases is 1.5,the abrasive tool achieves the best processing effect,the minimum surface roughness of workpiece is 0.05 μm.(4)In view of the problem that the abrasive grains are easy to fall off in the current processing of viscoelastic magnetic abrasive tools,the magnetic field generating device is improved.Based on the principle of magnetic circuit design,the single pole size is calculated,and four pole layout schemes are designed.Through software simulation and analysis,the magnetic distribution of different layout schemes is compared.After comprehensive consideration,Haier Baker array is adopted,and then other components of the magnetic field generating device are designed.Through the experimental verification,in the new magnetic field environment,the original problem has been effectively improved. |
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