Wear Characteristics of Vitrified cBN Grinding Wheels

To clarify the wheel wear characteristics in grinding process using vitrified cBN wheels, we have investigated the change in wheel wear behavior when the load on the grain cutting edge is increased by increasing work speed. Wheel wear behavior in the grinding process may be classified into two main types, a) wheel wear process-type 1, that is consists of initial and steady-state wheel wear regions, and b) wheel wear process-type 2, that is consists of initial, steady-state and abnormal wheel wear regions. In the steady-state wear region of wheel wear process-type 1, lower wheel wear rate, lower stable grinding forces and good finished surface roughness are obtained, because self-sharpening due to micro fractures of the cutting edges takes place. In grinding with wheel wear process-type 2, it is very hard to obtain good finished surface and high grinding ratio, because of occurrences of fracture or releasing of cBN grains.