Correlation of the wear characteristics with abrasion resistance factor—1/(vol. loss) in a standard test—has been established in a low speed range where the temperatures involved in the cutting action are relatively low. It was found that a lower abrasion resistance factor produced, (in specified time and cutting conditions except speed, which was a variable), higher flank wear at a range of low speeds—20 to 100 SFPM or 6 to 55 per min—but, when speed is increased, other properties than abrasion resistance are involved, i.e., hot hardness characteristics and thermal conductivity coefficient are able to withstand higher velocities. Speed versus thermal conductivity coefficient curve was established where the cutting time and flank wear levels were constant. Feed and depth of cut were also constants. The investigation demonstrated that thermal conductivity coefficient of the cutting grade material is very significant and plays a major role in its ability to resist transfer of heat from the cutting zone to the flank of the tool, and thus no reduction of hardness due to temperature. This phenomenon results in the ability of the tool to perform in high speed range.

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