Theoretical And Experimental Study On Energy Partition Of CBN Wheel Grinding Narrow-deep-Groove

Narrow-deep-groove mainly refers to a special structure that exist on aviation,automotive and hydraulic pump parts,with large width-depth ratio.This structure which requires high processing accuracy is often made of poorly machined materials.So the processing of this structure has been the field of mechanical processing problems.The introduction of the Single-layer electroplated CBN wheel grinding narrow-deep-groove technology,makes high-quality and efficient processing possible.In order to reduce and control the grinding temperature,preventing grinding burn,it is necessary to establish a energy distribution theory that is suitable for the processing of single layer CBN wheel grinding narrow-deep-Groove.The energy distribution and temperature distribution of the workpiece during machining provides the theoretical basis for the targeted cooling.In this paper,the classical theory of grinding heat distribution is analyzed and compared.Considering the influence of the electroplated metal bond on the heat transfer and absorbing capacity of the grinding wheel.The abrasive grains and the coating are regarded as the composite body,and the Effective Medium Theory is introduced to correct the grinding energy distribution theory of Malkin.Temperature measurement circuit and related fixture is designed.The experimental platform for grinding force and grinding temperature measurement is established.The experimental program of single layer electroplated CBN grinding wheel is designed and carried out.The influence of different grinding parameters on grinding force and grinding temperature is analyzed.The results show that the grinding force and the grinding temperature change trend gradually increase when the grinding depth and feed rate increase.With the increase in the speed of the grinding wheel,the grinding force gradually becomes smaller and the grinding temperature increases.The change in grinding depth has the greatest effect on the grinding temperature,followed by the feed rate,and the grinding wheel speed is the smallest.The energy distribution ratio of the workpiece under different grinding conditions is calculated according to the modified grinding energy distribution theory.Based on the calculated results and the grinding force data,the APDL program is written to complete the three-dimensional finite element simulation of the transient temperature of the single-layer plated CBN grinding wheel,and the temperature distribution is obtained.Compared the simulation data with the experimental data,it is found that the experimental temperature curve and the simulated temperature curve has similar variation tendency on different grinding parameters at the groove bottom area,and the deviation at the whole grinding stage is small,The deviation of the maximum temperature is only 1.6%~12.6%.It is indicating that the heat source model and heat flux value which applied to the grinding arc area in the simulation is closer to the practical grinding process,which verified the correctness of the grinding energy distribution theory.The simulation results and experimental results of the groove side area at the process of CBN wheel grinding the narrow-deep-groove is compared.It is indicated that the trend of the two results is consistent.But the deviation is large.And the contact process between the grinding wheel and the narrow-deep-groove in the CBN grinding wheel is further analyzed.The finite element model is created and simulation is carried out.The simulation results show that there are energy transfer between the grinding wheel and the workpiece in the side wall area.The simulation results show that the main influencing factors are the depth of grinding,the energy distribution ratio of the workpiece and the contact length of the side contact area.