MEASUREMENT OF FORCES DURING CUTTING WITH A SINGLE ABRASIVE GRAI

Abstract

The forces that occur between a single grain and a workpiece during the cutting process have been measured by two methods. In one, a dynamometer which utilizes piezoelectric elements measures both the tangential and normal components of force, a small workpiece on the dynamometer being subjected to single grain cutting. In the other method, a single abrasive grain is mounted on a rotating member, the change of angular speed of which is measured during the cutting process. This speed change can be related to the average tangential force between the abrasive grain and the workpiece during the cutting process, although, in the present work, it is used directly to find the work of cutting. To determine the response of the dynamometer, and to calibrate it, small steel balls have been bounced off the workpiece, and the output of the dynamometer compared with the pulse shape that has been determined analytically. Included are oscilloscope traces showing the response of the dynamometer during the bouncing bait calibration, and during cutting. Results include values of energy expended in cutting as determined by both procedures.