Preparation Process And Experimental Study Of Bonded Magnetic Abrasives Based On Solid-Liquid Mixing And Direct Molding

Magnetic abrasive finishing is a non-traditional technology to improve the surface quality of workpices.It has the advantages of excellent processing effect,high processing efficiency,no change in the size and shape precision of the workpieces,which has caused extensive research at home and abroad.As a tool of this processing technology,magnetic abrasives are the key factor of affecting the processing quality and efficiency of workpices.The finishing performance and service life of the magnetic abrasives are closely related to the preparation process.Therefore,the preparation of magnetic abrasives has become a key problem in the development of the magnetic abrasive finishing technology.Compared with the other magnetic abrasive preparation processes,the bonding method has the advantages of simple process and low cost.But,there are some following problems during the preparation of magnetic abrasives by the method of bonding in the current process:magnetic media,abrasive particles and resin are difficult to mix evenly,which is not only difficult to operate,but also leads to excessive use of resin frequently.In addition,mechanically crushing is used to obtain magnetic abrasives in the preparation process.But it is difficult to control the kynamics of the crushing machine,the strength of the resin matrix becomes larger when it completely cure,this increases the difficulty to further broken;in the process of crushing,the abrasives would be decoupled from the ferromagnetic powders,and a lot of useless fine powders are produced at the same time,this would result in wasted.According to the above problems in the preparation process of magnetic abrasives,a kind of bonding preparation process is put forward in this paper.In order to avoid the wasting caused by the crushing and improve the quality of mixing between ferromagnetic powders,abrasive powders and resin,the mechanical stirring and extrusion molding method are used in the preparation of magnetic abrasives to make sure that the ferromagnetic powders and abrasive powders can disperse uniformly in the solvent under the action of physical dispersion.The main contents are as follows:(1)The existing problems in the preparation of bonding magnetic abrasives process are analyzed.Based On the theoretical analysis,a technical scheme for the preparation of magnetic abrasives with solid liquid-mixing is proposed,and the verification test is carried out.Finally,the preparation process of bonding magnetic abrasives with solid-liquid mixing is determined.(2)The structure design and finite element analysis of the magnetic abrasive forming device are carried out by SolidWorks and ANSYSWorkbench software,and the two magnetic abrasive forming schemes are compared by theoretical and processing performance experiments.The results show that the scheme of preparing magnetic abrasives at the bottom of the barrel is superior to the scheme of preparing magnetic abrasive powders at the side of the barrel.The magnetic abrasive powders prepared at the bottom of the barrel have a good performance.The roughness Ra value decreases from the initial 0.875?m to0.061?m,and the Rz value decreases from the initial 4.31?m to 0.52?m.(3)Taking the 45~#steel tubes as the workpice,the experimental study on the finishing of the steel tube outer surface was carried out.Compared with the magnetic abrasives prepared by the solid-solid mixing process,the solid-liquid mixing magnetic abrasives have a more excellent performance of magnetic abrasive finishing.After 10min,the roughness value of Ra was decreased from0.800?m to 0.076?m;MRR was 0.67?m/min with the 40 mesh magnetic abrasives prepared by the proposed preparing process Secondly,the performance index of magnetic abrasives was tested,The solid-liquid mixing magnetic abrasives have good microstructure and long service life.(4)With different magnetic abrasive powders,an experimental study was carried out,in which 6061 aluminum alloy tube was used as the research object.The results show that the solid-liquid mixing magnetic abrasives have a more excellent performance of magnetic abrasive finishing,compared with the magnetic abrasives prepared by the solid-solid mixing process,when the magnetic poles were arranged as 90 degrees.(5)With different magnetic abrasive powders,an experimental study was carried out,in which TC4 titanium alloy plate was used as the research object.The results show that the solid-liquid mixing magnetic abrasives have a more excellent performance of magnetic abrasive finishing,compared with the magnetic abrasives prepared by the solid-solid mixing process.(6)Orthogonal experiments were conducted to study the effects of the preparation parameters,the speed of the press bar,the reciprocating motion frequency and the amplitude of reciprocating motion,on the finishing performance of the magnetic abrasive powders during the preparation process of the magnetic abrasive powders.According to range analysis,the order of influence of each parameter on the finishing performance of magnetic abrasive grains is obtained.From the results of variance analysis,the article find that the each parameters and interaction between parameters has no significant effect on the finishing performance of magnetic abrasive powders.