Detection for Cutting Tool Fracture by Acoustic Emission Measurement

Summary The acoustic emission signal from the cutting process was monitored in order to investigate feasibility of in-process detection of tool failure during metal cutting. Interrupted cutting of alloy steel SCM3(JIS) was carried out with carbide tools F20 and ceramic tools on an NC lathe, and acoustic emission signals with large amplitudes were detected when cracking, chipping and fracture of the cutting tools were observed. The feed motion of the lathe was automatically stopped when the damages of the tools were detected. The amplitude of detected acoustic emission signal was related to the damages of the tools, however it was not much influenced by the cutting conditions under investigations. The acoustic emission signals associated with fractures of the tool materials in both indentation tests of a diamond indenter and transverse rupture tests were also measured for different tool materials to investigate the basic characteristics of the acoustic emission signals in fracture processes. Correlations of the acoustic emission signals in both the cutting tests and the tool fracture tests were also discussed.