Development Of An Internal Cooling Grinding Wheel For Circumferential Grinding And Research On Its Machining Performance

Grinding plays an important role in the processing and manufacturing of key components of aviation superalloy.In order to avoid adhesion,flaking,work hardening and other phenomena on the surface of workpiece caused by excessive grinding temperature when processing superalloy.In this study,the method of directional ejection of coolant from inside grinding wheel,i.e.directional internal cooling method,is used to enhance the cooling and lubrication effect of grinding area and increase the utilization rate of coolant.In addition,various surface slotting structures have been designed to improve the poor grinding heat exchange and blockage problems that often occur in traditional surface structure grinding wheels.In this paper,considering working performance of the grinding wheel,a new type of internal cooling grinding wheel for circumferential grinding is designed and prepared by combining directional internal cooling technology with surface slotting technology,and its strength,stiffness and internal flow field are checked.According to the existing conditions and the characteristics of grinding wheel,the vertical Circumferential grinding experiment of nickel-based superalloy has carried out under the condition of directional internal cooling.And compare it with external pouring cooling method.The influence of surface slotting structure and liquid supply pressure on grinding temperature and surface quality of grinding wheel are explored.The main research contents are as follows:(1)Based on the circumferential grinding and directional internal cooling,and consider the existing conditions,a new type of internal cooling grinding wheel for vertical circumferential grinding is designed to improve the utilization rate of coolant.Meanwhile,in order to further reduce the generation of grinding heat and avoid blockage of grinding wheel;explore the existing research on slotted grinding wheel,and consider the structural characteristics of the designed cooling wheel,various surface slotting patterns(slotted A～slotted D/unslotted)are designed on the surface of grinding wheel,and the grinding continuity is analyzed accordingly.(2)The strength and rigidity of the designed internal cooling grinding wheel are checked by finite element method to ensure its stability and reliability during grinding.Computational Fluid Dynamics(CFD)method is used to simulate the flow field inside the grinding wheel,which is difficult to observe in situ,and to provide basis for subsequent grinding test scheme setting.(3)The assemblability and sealing ability of the designed internal cooling grinding wheel is preliminary verified by 3D printing.The grinding wheel matrix and abrasive ring are prepared according to the design requirements,and the round jumpiness test and directional injection performance inspection are carried out under static and rotating states.(4)Based on the existing experimental conditions,the construction of vertical Circumferential grinding test platform with directional internal cooling were complete;The grinding test scheme is formulated,and then the vertical Circumferential grinding test of nickel-base superalloy with directional internal cooling is carried out and compared it with external pouring cooling.The influence of liquid supply pressure and surface slotting structure on grinding performance of the internal cooling grinding wheel is explored.