Zones and boundaries between different types of chip

Abstract

The machining conditions, speed, feed and depth of cut, as well as the mechanical properties of the machined parts have a marked influence on the mechanics of chip formation. Different types of chip may be produced, namely continuous, partially discontinuous, discontinuous or continuous with either a serrated or a built-up edge. In the present work three different materials, aluminium, mild steel and brass, were machined orthogonally under different cutting conditions. Different types of chip were observed and the variations in the zones of and in the boundaries between types of chip with the machining conditions were determined for the materials used. An analysis for changing from one type of chip to another type is given, and recommended cutting conditions are reported for the different materials tested according to the type of chip produced. The cutting force components were measured in order to determine the mean coefficient of friction on the tool face and to determine the relation between this coefficient of friction and the type of chip produced.