Acoustic emission study of surface deterioration in tribocontacting

- Acoustic emission (AE) was studied in the course of chip formation.
- AE waveforms were analyzed using the STFT-obtained median and central frequencies.
- The median frequency drops at the moment of chip formation by cracking.
- Strain field pattern determined the chip formation type.
- The AE burst corresponded to shear fracture mode.

This paper is devoted to studying an acoustic emission (AE) response to the type of low speed chip formation in cutting ductile metals with the use of a purpose built rig. The workpiece surface patterns obtained after both continuous and discontinuous chip separation have been analyzed together with the AE single frame amplitude and frequency-domain parameters. It was found that the median frequency time-dependence shows a drop in case of a discontinuous chip separation. This result has been discussed with the involvement of strain distribution maps and fracture modes responsible for the type of chip formation.

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