MODELING AND ANALYSIS OF ACOUSTIC-EMISSION IN DIAMOND TURNING

To estimate the acoustic emission (AE) energy released in diamond turn ing, a quantitative model, which contains the energy from primary, sec ondary, tertiary cutting zones and the rubbing zones, is proposed and compared with experimental data. The purpose of this model is to assis t in process characterization and monitoring. As part of the model dev eloped here the plowing energy, that is, the energy released in the te rtiary zone, is approximated by the forming load in the rolling proces s where the roller is stationary. This load is theoretically calculate d by the upper bound method and used in the estimation. A series of di amond turning tests were conducted to check the validity of the model. It was found that the energy content of the AE signal is close to the theoretical predictions. The spectral analysis of the AE signal in th ese tests is also carried out. It was noticed that when the diamond to ol first touches the workpiece without producing any chip, more high f requency components were observed and this stage was recognized as the rubbing stage. The results further support the previous findings, tha t is, that abnormal rubbing always increases the mean frequency of the raw AE signal.