Grindability Study of CBN Wheels

The results of a series of plunge surface grinding tests conducted with CBN wheels on fully heat-treated bearing steel showed that the increase in G ratio, compared with Al2O3 wheels, can be a factor of 20 to 200 times. Assessment of grindability in terms of grinding forces, specific energy, surface finish is discussed over a grinding wheel speed range from 20 ms to 60 m. The effects of grain size and grinding conditions are also presented, together with spectral analyses of the process-generated dynamics. For a given workpiece-machine system* CBN wheels exhibit unique characteristics that the grindability will increase with time for all the tests conducted.