• Reuben, Bob
• Ward, C. R.
• Lamb, J.
• Wilkinson, P.

Abstract

<p>The overall aim of this work is to establish whether the processes which cause surface residual stresses during the CNC turning of difficult-to-machine materials generate identifiable acoustic emission (AE). If successful, this would offer an industrially robust technique for assessing the quality of high added-value machined components as defined by the surface finish and the residual stress induced by the machining process. The research involves machining metastable austenitic stainless steel under different cutting conditions to promote stress-induced austenitemartensite phase transformations. This phase change introduces surface residual stresses by virtue of the volume change, which can seriously affect the service life of manufactured components. The interim conclusion of the work is that AE generated during machining appears to be related to the measured surface residual stress, although further work is required to establish whether the generating mechanism is the intensity of the mechanical contact or the martensitic transformation itself.</p>

Topics

• impedance spectroscopy
• surface
• stainless steel
• phase
• acoustic emission