Material Removal Characteristics And Quality Control Approaches In Grinding Of Thin Disc Blade

Cemented carbide thin-walled disc-shaped round blades are widely used in cutting paper,fiber,rubber and other processes.Aiming at solving the problems of low processing efficiency and poor processing quality in semi-automatic grinding,this paper studies the material removal mechanism in the processing of ultra-fine cemented carbide ultra-thin round blades,and establishes a creation model for grinding surfaces.A grinding test-rig has been set up with optimized processing plan.The deformation behaviors of the disc blades during grinding were investigated due to low bending rigidness.The methods for edge surface quality control were proposed to improve the profile accuracy and service life of disc tools.The main research results can be summarized as follows:Firstly,the material removal mechanism of superfine carbide blade grinding was studied.The matched grinding wheel model was selected according to the material characteristics of ultra-fine cemented carbide.Based on the analysis of local micro-grinding characteristics of thin-wall disk blade grinding,the finite element model of single abrasive cutting was established by combining the constitutive equation and failure model of the material.The minimum undeformed cutting thickness of the material was obtained by simulation experiment,and the correctness of the model was verified by single-point diamond scratch experiment.On this basis,the simulation experiment of reciprocating grinding with multiple abrasive particles was carried out,and the material removal characteristics of parallel and cross scratches were studied.By comparing the surface morphology of the grinding surface,the mechanism model of the surface formation of the cutting edge of the disk cutter was developed.Secondly,a thin-walled blade grinding test-rig was built to examine the grinding effect in two kinds of edge grinding modes: face grinding and cylindrical grinding.The structural characteristics and edge profile of thinwalled disc blade was analyzed for fixture and tooling plan.The dynamic performance of grinding process system was investigated to verify the stability of grinding process.It is revealed that the face grinding method can bring lower surface roughness because of better contact rigidity,which is taken as the preferred grinding mode for disc blade processing.Followed,a compensation model of blade contour error for batch machining of thin-walled disc blade was established.The edge profile error of the round blade was analyzed based on 3D contour measurement.The nonlinear function of the blade profile error due to elastic deformation and nominal cutting depth is developed.A tool error compensation model for edge grinding is proposed.The origin secant algorithm is selected as preferred compensation method by comparing the four iterative calculation.Two compensation strategies named as depth compensation and angle compensation were proposed respectively.The angle compensation was found to be more efficient as compared with depth compensation by means of experimental comparison.Finally,the method to improve the surface roughness uniformity of ground blades was proposed.The influence of the bowl wheel inclination angle and the wheel grain size on surface quality of the ground blades were examined.The relationship between surface texture and grinding parameters was established through kinematic analysis.The effects of dual-region grinding,single-region grinding,and cutting point density on surface morphology were investigated respectively,based on the microstructure and surface roughness of the blade cutting edge measurements with the confocal optical 3D profilometer.It is revealed that single-region grinding can result in better surface consistency while dualregion grinding accounts for better roughness.For finish grinding of disc blades,single-region grinding without crossing texture should be adopted with fine feeding.