STUDIES ON TRUING AND DRESSING OF DIAMOND WHEELS .2. TRUING MECHANISM OF METAL BONDED DIAMOND WHEELS WITH THE GC CUP-TRUER

In the first report, a new technique for measuring the protusion height of abrasive grains was proposed so that the grinding performance of diamond wheels could be evaluated correctly. The present report investigates the truing mechanism of matrix-type wheels, paying special attention to the behavior of the bond material around the diamond cutting edges. The bond material was found to be removed by GC grains broken off from the cup-truer. The main results obtained are as follows: (1) Both truing and dressing are performed simultaneously with the GC cup-truer due to the lapping action of the loose GC grains. (2) Lapping can be improved by minimizing the outflow of loose GC grains during truing by controlling the amount of coolant supplied to the truer. (3) The mean protrusion height depends on the truing conditions after a set number of truing and dressing passes have been made. (4) An increase in the size of the GC grains enhances the lapping action in the truing process and results in an increase in the truing ratio and an increase in the mean protrusion height.