Measurement of Wear of Twist Drills

Abstract

The results of a number of wear tests using the new surface activation technique are described. The technique itself has been refined to allow greater sensitivity and a quantitative interpretation of the results in terms of an equivalent linear wear. Calibration curves of wear against loss of radioactivity have been obtained both directly by grinding and indirectly by prediction from a separate measurement of activity as a function of depth. Agreement between optical and surface activation measurements is good. The sensitivity of the surface activation technique has been exploited to obtain new results for the very early stages of flank wear.