Research On The Material Removal Rate Of Workpiece Surface Based On Abrasive Grain's Kinematic Trajectory Of Double Disc Grinding

The concept of industry 4.0 is triggering a new round of manufacturing innovation worldwide,and the development level of manufacturing reflects a country's economic and technological power.Grinding is an important processing technology in precision and ultra precision machining.Compared with traditional grinding,double disc grinding has developed rapidly in recent years for its high precision,high efficiency,high automation and wide processing range.However,double disc grinding processing still exists many problems restricting its further development such as grinding wheel passivation,grinding burn and so on.This paper deals with the nonuniform material removal and overproof of flatness occurred on the workpiece surface in double disc grinding processing.To solve that problem,this paper establishes three models,based on the kinematics analysis of double disc grinding.Following that,the effects of processing parameters on the removal rate of workpiece surface are analyzed.Through theoretical analysis and experimental study,the solutions are put forward.The concrete research contents are as follows:(1)The distribution model of abrasive grains on the double disc grinding wheel is established.This model is a basic model in this paper,which involves three main factors of abrasive grains:shape,dimension and location.In order to make the model accordant with actual circumstances as well as possible,the shape of the abrasive grains in the model is set to sphere based on the actual working conditions,the dimension of the abrasive grains is set a non-Gaussian random distribution,and the location of the abrasive grains is added a random shaking for appropriate number in the x,y and z directions.The establishment of this mathematical model lays a foundation for subsequent analysis.(2)On the basis of the distribution model of abrasive grains on the double disc grinding wheel,the model of abrasive grains' kinematic trajectory on the workpiece surface is established.Via coordinate transformation,it is obtained that the kinematic trajectory of any abrasive grain in the workpiece coordinate system.Next,the analysis is conducted that the variation rules of single abrasive grain's trajectory with speed ratio under co and counter rotation of grinding wheel and workpiece.Then the periodicity of abrasive grain's trajectory is studied,as well as its negative influence and elusion measures.Finally,the distribution of multiple abrasive grains' trajectories under co and counter rotation as well as different speed ratios are analyzed by the trajectory density method.(3)Coupled with the distribution model of abrasive grains on the grinding wheel and the model of abrasive grains' kinematic trajectory on the workpiece surface,the overall distribution model of material removal rate is established,which is based on kinematic analysis.After that,the variation rules of material removal rate on the workpiece surface with speed ratio of single and multiple abrasive grains are obtained.This model can directly reflect the material removal results on the workpiece surface after double disc grinding as well as the processing parameters'influence.At last,the corresponding rules are summarized and the solutions are put forward.(4)Seeing the theoretical analysis is accomplished,the corresponding experiment study is carried out to measure the height distribution of workpiece surface under different speed ratios.The experiment is carried out in several groups according to different speed ratios.The height differences of several selected points on the workpiece surface are measured and the final experimental data are analyzed.Finally,the distribution rules of material removal rate on workpiece surface are obtained.Here is this paper's conclusion:quantified variation rules of single abrasive grain's tarjectory length with different speed ratios,as well as critical speed ratio and limit trajectory length.The periodicity of abrasive grain' trajectory,as well as its negative influence and elusion measures.Variation rules of multiple abrasive grains' trajectories distribution with different speed ratios,and the condition for uniform trajectories distribution.Material removal rate on the workpiece surface of single abrasive grain.The overall material removal rate of multiple abrasive grains.Finally,it is put forward that the measures to avoid center bulge phenomenon and optimize the flatness of the workpiece.This research is not only helpful to promote the accuracy and optimize the parameters of double disc grinding processing,but also good for the theory improvement,the technology development and further research in the double disc grinding field.