| 摘要 |
A method for machining a high temperature nickel based alloy workpiece or other difficult-to-work material. The method involves machining the workpiece at an effective cutting speed of up to about 1500 sfm per minute, moving a ceramic-metal cutting tool across the face of the workpiece at a rate of up to about 0.04 in/rev, and cutting the workpiece with the ceramic-metal cutting tool to effect a depth of cut of up to about 0.15 inches per pass. The ceramic-metal cutting tool has a density of at least about 95% of theoretical, and includes about 80-98%, preferably 88-96%, by volume of granular hard phases and about 2-20%, preferably 4-12%, by volume of a metal phase. The granular hard phases are (a) a major hard phase portion of alumina and (b) a minor hard phase portion of hard refractory metal carbides, nitrides, carbonitrides, and borides. The metal phase is combination of nickel and aluminum having a ratio of nickel to aluminum of from about 80:20 to about 90:10, preferably 85:15 to 88:12 by weight with optional additives. Preferably, the metal phase is non-continuous and dispersed, and at least a major portion of the metal phase is segregated at hard phase triple points.
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