ALUMINA-BORON CARBIDE CERAMICS AND METHODS OF MAKING AND USING THE SAME

摘要

A method of machining a workpiece including the steps of providing a workpiece; providing a ceramic cutting insert having a rake surface and a flank surface wherein the rake surface and the flank surface intersect to form a cutting edge and the ceramic cutting insert having a substrate that comprises between about 15 volume percent and about 35 volume percent of a boron carbide phase and at least about 50 volume percent alumina and has a fracture toughness (K_IC, 18.5 Kg Load E&C) greater than or equal to about 4.5 MPa.m^0.5; causing relative rotational movement between the workpiece and the ceramic cutting insert wherein the surface speed of the relative rotational movement is equal to or greater than about 457 surface meters per minute; and bringing the ceramic cutting insert and the workpiece into contact with each other so as to remove material from the workpiece.