Influence Of Both Surface Roughness Of Carbide Inserts And Cutting Parameters On Residual Stresses In Thin-Walled Cylinder Turning

Thin-walled parts have the characteristics of light weight,complex structure,poor rigidity and easy deformation.It is widely used in aerospace,ship,automobile and other fields.However,the residual stress is easily produced on the surface of thin-walled part during cutting.Distribution and redistribution of residual stress cause severe deformation during blank making,processing and later aging.It causes the geometric size error and shape and position error to get out of control,and even result in product scrapping.For this reason,how to improve the friction conditions between the tool and the chip during cutting,and to realize the prediction and control of the residual stress on the surface of the workpiece are particularly important to improve the quality of the product.Therefore,this paper adopt improving the roughness of the inserts surface and selectting the reasonable cutting parameters to reduce the friction coefficient between the cutting tool and the chip,so as to improve the distribution of the residual stress on the surface of the workpiece.Particularly the cemented carbide inserts with different surface roughness were prepared by chemical mechanical polishing(CMP),the finite element simulation,cutting force turning experiment and test experiment of residual stress are utilized to achieve the coefficient of friction between the inserts surface and the chip,analyze the influence of inserts surface roughness and cutting parameters on residual stress of workpiece surface and launch the simulation analysis of subsequent cutting deformation based on established residual stress field of turning.The main research works are as follows:1)Different surface roughness inserts is Prepared.Three groups of inserts with different surface roughness by rough polishing,rough polishing+semi-polishing and rough polishing+semi-polishing+polishing are prepared through CMP multiple processes,then the surface morphology of each inserts are observed by microscope.2)The actual friction coefficient between the surface and chip of different surface roughness is determined.First,the relationship between the friction force and the friction coefficient of the inserts with different surface roughness under different cutting parameters is obtained by the finite element simulation experiment of the AdvantEdge cutting force.Combined with cutting force turning experiment,the actual cutting coefficient of friction of inserts with different surface roughness corresponding to cutting parameters are obtained.3)The influence of different inserts surface roughness and corresponding cutting parameters on cutting residual stress.First,the residual stress values of the workpiece surface with different surface roughness and corresponding cutting parameters were obtained by finite element software AdvantEdge FEM.Then,the residual stress on the workpiece surface is measured by x ray residual stress measuring instrument and the influence of inserts surface roughness and cutting parameters on the residual stress of machined surface is analyzed.Finally,an empirical formula for residual stress of workpiece surface is established.4)The residual stress field based on different surface roughness inserts and cutting parameters is used to simulate the deformation of thin walled cylinders after subsequent turning.The thin-walled cylinder parts are set up by the finite element software ANSYS Workbench.Surface residual stresses corresponding to different surface roughness inserts and cutting parameters on the surface is applied to the surface,the cutting process is simulated with the help of the life and death unit technology,and the influence of the residual stress on the deformation of the thin-walled cylinder in the subsequent turning with different surface roughness inserts and cutting parameters is analyzed.In conclusion,this study will provide a theoretical reference for revealing the influence of inserts surface roughness and cutting parameters on the residual stress of thin walled cylinder turning.