On the Effects of a Built-Up Edge on Acoustic Emission in Metal Cutting

Abstract

Experimental evidence is presented which indicates that the presence of a built-up edge can significantly affect the generation of acoustic emission in metal cutting. Results for machining SAE 1018 and 4140 steels show that the built-up edge can mask the generally accepted AE-cutting speed relation when cutting tools having small rake angles are used. Under cutting conditions conducive to development of a built-up edge, it is shown that increased acoustic emission is generated as a result of increased effective rake angle and corresponding increase of shear angle in the primary deformation zone. Three distinct types of built-up edge have been observed and classified as immature, periodic, or developed, according to effect on acoustic emission.