Research On The Surface Quality Of The Component In High Speed Point Grinding

With the rapid development of national economy, the advanced manufacturing technology is promoting toward high speed, efficient, high precision.Grinding process is very important in the field of mechanical manufacturing process,because it may obtain high machining accuracy and surface quality. High-speed point grinding is a kind of high efficiency and high flexible machining technique that is integrated of numerical control technology, super-hard abrasive technology and high-speed grinding technology.Its grinding wheel axis is revolved to workpiece axis in horizontal and vertical direction to form point contact in theory.Point grinding is very different from ordinary grinding,and it has the advantages of low grinding temperature and grinding force. At present its core technology and theory has not been mastered in the domestic. So it is necessary to research and develop the key theory and technology of the technique.Surface quality of the parts is an important index to measure the processing technology.The research about theory and technologyof point grinding quality control is very few. Therefore this paper carry on research about point grinding technology in the microstructure characteristics, temperature field of the grinding contact area and the influence of surface quality to fatigue strength.According to the generate mechanism of the grinding surface, a mutual interference model between grinding wheel and workpiece is established.The grinding surface microstructure of the part is simulated from perspectives of kinematics.The surface micro-topography of part after grinding is simulated in different grinding machining parameters,and the influence of grinding machining parameters to surface roughness is analysed.In order to research the influence of grinding variables angle to surface roughness, a lot of grinding experiments are carried out under the condition of different variables angles and different material. Through measuring surface roughness and observing surface microstructure, surface micro-topography of different grinding variable angle is analysed.Then the workpiece of different grinding parameters is grinded in selected grinding variable angle. The influence of different grinding conditions to surface micro-topography is analysed to optimize the grinding process of point grinding.Thermodynamics transfer model of point grinding is analysed and established,and the mathematical model of grinding surface temperature distribution of point grinding is calculated using segmentation and iterative method. To obtain a more distinct grinding temperature distribution,a heat conduction model between grinding wheel and workpiece is established, and temperature field distribution of point grinding is obtained.With the purpose of analyzing the influence of the surface quality to fatigue strength, fatigue specimens are machined in different grinding variable angle. The fatigue life of fatigue specimen in tensile condition is caculated using fatigue analysis software, and the fatigue test of fatigue specimen under dissymmetric cycle load is carried out, and the cycling times is obtained. The influence of grinding variable angle to fatigue strength is analyzed on the basis of simulation and experimental results.