| Aluminum alloys and and its plate play an important role in national production and life,its surface quality determines the workpiece efficiency and service life,the traditional surface finishing method has some defects which are difficult to overcome when finishing the surface of the metal sheet.Fluid Magnetic Abrasives is a new type of finishing tool with magnetorheological properties and has been used to finish the surface of curved surface parts.There are different requirements for processing flat workpieces compared to curved surface parts:(1)Abrasives requires large-grained solid-phase particles(more than 10μm),there is no practical study on the formulation of Fluid Magnetic Abrasives using large-grained solid-phase particles and the effective preservation technology;(2)The existing finishing equipment cannot efficiently use the magnetic field,moreover,its structure is not suitable for processing flat workpieces.In order to solve these problems to make Fluid Magnetic Abrasives finishing process get a new developments in the finishing of the surface of flatworkpieces,this paper will start with the theoretical analysis of the Fluid Magnetic Abrasives,then the Fluid Magnetic Abrasives and finishing equipment will be studied.This paper makes research on the following aspects:1)The domestic and international progress of surface finishing technology of Fluid Magnetic Abrasives are reviewed.It is proposed to carry out surface finishing of aluminum alloy sheet by Fluid Magnetic Abrasives and carry out research and analysis.2)By studying the microscopic mechanism of surface finishing of Fluid Magnetic Abrasives and combining with the material removal model,it is proposed that the larger the diameter of solid particles and the magnetic field intensity,the greater the force of Fluid Magnetic Abrasives on the surface of the workpiece,and the higher the surface metal removal,the higher the finishing efficiency.Based on this,the conditions for improving the surface finishing efficiency of the workpiece are proposed.Firstly,a new type of Fluid Magnetic Abrasives finishing equipment should be designed properly,secondly,a new Fluid Magnetic Abrasives with large-grained solid-phase particles should be prepared.3)The Fluid Magnetic Abrasives finishing equipment was designed,it includes magnetism installation and power plant.After theoretical analysis and magnetic field simulation,it is proposed to arrange the Tegular Permanent Magnet on the plastic plate by means of mosaic distribution,so designing the Apposite Magnet Pole that the end faces are arranged relative to each other,which concentrate magnetic energy in the processing area and make the magnetic line perpendicular to the workpiece,this increases the grinding force of Fluid Magnetic Abrasives on the workpiece surface.The 3d model of the power plant is drawn,and the power plant is reconstructed on the basis of the milling and drilling machine,the functions of adjusting the rotation speed of the magnetic pole,adjusting the distance between the magnetic pole and the reciprocating motion of the workpiece are realized.The surface finishing device based on fluid magnetic abrasives was used to perform proof processing experiments on the 6061 aluminum alloy plate.The results show that the Apposite Magnet Pole increase the grinding force of the Fluid Magnetic Abrasives to the workpiece and improve the finishing uniformity and finishing efficiency,but the rotational speed of the magnetic pole cannot be increased indefinitely,the appropriate rotational speed should be selected according to the surface quality requirements of the workpiece.4)A new Fluid Magnetic Abrasives preparation process was developed,and the Fluid Magnetic Abrasives with large-grained solid-phase particles was prepared.Different formulation schemes are proposed depending on the dispersing agent.After Fluid Magnetic Abrasives are prepared,the schemes are evaluated by picture of real products,natural sedimentation and stir force.it is found that the mixed solution prepared by distributing the 107 room temperature vulcanized rubber and the polishing liquid in the water as a base liquid is the optimal preparation scheme in a natural static state.A new preservationtechnology is proposed from a practical perspective,which is a method of suspending a permanent magnet on the top of the container.Through the observation of sedimentation and the comparison of stir force,it is concluded that it is most advantageous to save the Fluid Magnetic Abrasives by using new preservation technology.The finishing experiment of 6061 Flat Aluminium Alloy Plate was carried out by using new Fluid Magnetic Abrasives,and the influence of the gap between the upper and lower magnetic poles on the finishing effect is analyzed.The results show that when the rotational speed of the magnetic pole is 606r/min,the surface finishing effect is best under the condition that the ends gap between the upper and lower magnetic pole is 2mm.5)The orthogonal method was used as the experimental scheme design,the experiment analysis adopt the reduction percentage of surface roughness as response.The effects on the surface roughness of the workpiece of the Magnet Pole rotational speed,the workpiece feed speed,the gap between the upper and lower Magnet Pole and finishing time were investigated.Through the range analysis of the experimental results,the primary and secondary factors are ranked as:the gap between the upper and lower Magnet Pole,finishing time,the Magnet Pole rotational speed,the workpiece feed speed.Through the mean analysis of the experimental results,the influence law of each factor in the processing is detailed,according to this,the best combination of various processing factors is: the Magnet Pole rotational speed 345r/min,the workpiece feed speed 2mm/s,the gap between the upper and lower Magnet Pole 4mm,finishing time 36 min.The effectiveness of the optimal parameter combination is verified by finishing experiments. |
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