One method to monitor tool wear during turning process is based on the analysis of acoustic emission (AE) generated from the machining process. Different types of wear (tool flank wear and tool chipping) cause variation of different parameters of the measured AE. In the case of uniform abrasion of the tool flank, e. g. flank wear or crater wear, an enhanced mean signal level is found, whereas microbreakage at tool edge produces an increasing Crest factor.

The advantage of this AE based new method for monitoring tool life time becomes evident in the case of turning processes with low depth of cut, especially for monitoring finishing processes. The experimental results have laid down the basic requirements for a systematic process development aimed at the detection of tool wear during turning processes, which in particular applies for inferior chip depths. 1