METAL CUTTING FROM A MATERIALS VIEWPOINT.

Although metal cutting is one of the most widely used engineering operations, surprisingly little is known about the physical metallurgy of the process. The problem is one in which the plastic flow of the workpiece metal is only partially constrained and also one in which small volumes of metal are subjected to high rates of strain. In this review, the deformation structure of the chip is discussed with particular emphasis on the lamellar structure. Also, the separation of workpiece material around the tool nose is discussed in relation to built-up edge formation and the role of free machining additives in improving machinability. The influence of high temperatures generated at the chip/tool interface on the microstructure of high speed steel tools is discussed in terms of the effect on tool wear.