Determination of Flank Wear in Turning - An Acoustic Emission Approach

This analysis focuses on the online monitoring of flank wear in turning from the experimentally observed Acoustic Ernission signal. It is used as one of the indirect methods of monitoring flank wear in turning. As per the technique, Taguchi’s “Design of Experiments”, the minimum number of experiments to be conducted in this analysis is calculated, and the turning operations are performed as per the machining conditions shown in the orthogonal array. Since the direct measurement of flank wear at regular intervals of time during machining consumes more man and machine hours, the Acoustic Emission signal developed in the machining area is continuously recorded during machining as an alternative to the flank wear. The corresponding flank wear in all the test conditions with respect to time of 300 seconds are observed and recorded. When the value of Acoustic Emission signal tends to reach the unsafe limit corresponding to the flank wear of above 0.2mm, the operator is alerted to stop the process so as to replace the tool. This technique minimizes the tool cost without sacrificing the quality of the product. In this study, the empirical modeling technique using “Regression analysis” is also incorporated to develop the linear and non linear models for all test conditions. The experimental, optimized and predicted values of flank wear are compared and correlated with the experimental Acoustic Emission signal.