The dynamic force load in grinding process is considered as a crucial factor affecting the quality of parts,and a better understanding of the mechanism of force generation is conducive to revealing the evolution of ma...The dynamic force load in grinding process is considered as a crucial factor affecting the quality of parts,and a better understanding of the mechanism of force generation is conducive to revealing the evolution of material microstructure more precisely.In this study,an iterative blending integrating grinding force model that comprehensively considers the impact of grain size and dislocation density evolution of the material is proposed.According to the grinding kinematics,the interaction of grit-workpiece is divided into rubbing,plowing,and chip formation stages in each grinding zone.On this basis,the evolution of material microstructure in the current chip formation stage will affect the rubbing force in the next grinding arc through flow stresses,which in turn will influence the total grinding force.Therefore,the flow stress models in rubbing and chip formation stages are firstly established,and then the dislocation density prediction model is established experimentally based on the characteristics of grain size.The effects of the evolution of grain size and dislocation density on the grinding forces during the grinding process are studied by means of iterative cycles.The results indicate that the implementation of an iterative blending scheme is instrumental in obtaining a higher accurate prediction of the grinding force and a deeper insight of the influence mechanisms of materials microstructure on grinding process.展开更多
Surface topography is an important factor in evaluating the surface integrity and service performance of milling parts.The dynamic characteristics of the manufacturing system and machining process parameters significa...Surface topography is an important factor in evaluating the surface integrity and service performance of milling parts.The dynamic characteristics of the manufacturing system and machining process parameters significantly influence the machining precision and surface quality of the parts,and the vibration control method is applied in high-precision milling to improve the machine quality.In this study,a novel surface topography model based on the dynamic characteristics of the process system,properties of the cutting process,and active vibration control system is theoretically developed and experimentally verified.The dynamic characteristics of the process system consist of the vibration of the machine tool and piezoelectric ceramic clamping system.The dynamic path trajectory influenced by the processing parameters and workpiece-tool parameters belongs to the property of the cutting process,while different algorithms of active vibration control are considered as controller factors.The milling surface topography can be predicted by considering all these factors.A series of experiments were conducted to verify the effectiveness and accuracy of the prediction model,and the results showed a good correlation between the theoretical analysis and the actual milled surfaces.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.52275453).
文摘The dynamic force load in grinding process is considered as a crucial factor affecting the quality of parts,and a better understanding of the mechanism of force generation is conducive to revealing the evolution of material microstructure more precisely.In this study,an iterative blending integrating grinding force model that comprehensively considers the impact of grain size and dislocation density evolution of the material is proposed.According to the grinding kinematics,the interaction of grit-workpiece is divided into rubbing,plowing,and chip formation stages in each grinding zone.On this basis,the evolution of material microstructure in the current chip formation stage will affect the rubbing force in the next grinding arc through flow stresses,which in turn will influence the total grinding force.Therefore,the flow stress models in rubbing and chip formation stages are firstly established,and then the dislocation density prediction model is established experimentally based on the characteristics of grain size.The effects of the evolution of grain size and dislocation density on the grinding forces during the grinding process are studied by means of iterative cycles.The results indicate that the implementation of an iterative blending scheme is instrumental in obtaining a higher accurate prediction of the grinding force and a deeper insight of the influence mechanisms of materials microstructure on grinding process.
基金supported by the National Natural Science Foundation of China(Grant No.51905347)。
文摘Surface topography is an important factor in evaluating the surface integrity and service performance of milling parts.The dynamic characteristics of the manufacturing system and machining process parameters significantly influence the machining precision and surface quality of the parts,and the vibration control method is applied in high-precision milling to improve the machine quality.In this study,a novel surface topography model based on the dynamic characteristics of the process system,properties of the cutting process,and active vibration control system is theoretically developed and experimentally verified.The dynamic characteristics of the process system consist of the vibration of the machine tool and piezoelectric ceramic clamping system.The dynamic path trajectory influenced by the processing parameters and workpiece-tool parameters belongs to the property of the cutting process,while different algorithms of active vibration control are considered as controller factors.The milling surface topography can be predicted by considering all these factors.A series of experiments were conducted to verify the effectiveness and accuracy of the prediction model,and the results showed a good correlation between the theoretical analysis and the actual milled surfaces.
