Analysis On Mechanism And On-line Monitoring System Of Acoustic Emission Oriented To Precision And High Efficiency Grinding

With the development of science and technology,more and more people pay attention to the precision and high efficiency grinding which can meet the demands of modern machining technology.For high quality surface,people need to monitor the grinding machining process.For the present,traditional monitoring system usually use the signal of grinding force or vibration to control the process.But this kind of system can`t express the work condition effectively and accurately.The on-line monitoring system which based on the technology of AE(acoustic emission) provide a new way to control the surface damage and integrality of the components.So this kind of system has been the most promising method for monitoring the grinding machining process.This thesis take the technology of AE as emphasis and establish the on-line monitoring system faced to the precision and high efficiency grinding.We use the method based on the parameters and the waveforms to study on the signals of AE which are in different conditions.At last,we analyze the relationship between the signals of AE and the grinding force combining with the phenomena of the experiments.Also we study on the mechanism that the material removal and the energy change exert on the signals.By further studying,we also give the difference of the AE signals when grinding the different directions of the composite ceramics and elaborate the influence that the attenuation and the dislocation motion act on the AE signals.Through studying and discussion,we come to the following conclusion:Firstly, there are mapping relations between the parameters in the process of grinding and the effective values of the AE signals.This relations can reflect the energy change and removal regime in the grinding machining process.Secondly,when we change the parameters of grinding,the AE signals have the same changing direction with the forces in the process of grinding.This result indicated that AE signals can represent the physical quantities of the grinding.Thirdly,the level of brittle fracture and plastic deformation in the grinding machining process can be expressed by the energy equivalent in the different bands of the spectrum of the AE signals.Fourthly,grinding along the warp of the composite ceramics can get more steady surface.Finally,when monitoring the process of grinding the composite ceramics,the distance between the AE transducer and the AE source should be less than 80mm.These results above will exert a positive impact on the high quality surface of the work pieces in the process of the precision and high efficiency grinding.