The use ofthe ultrasonic activated coolant improves ground surface roughness compared with the use of erdinary coolant.From theevaluation ofchange in theworking surface condition, ithas been clarified that the ultrasonic aetivated coolant suppresses loading and whee] wear, and keeps the working surface condition well.Since the uItrasonic yibration increases the kinetic energy per width ofthe coolant, the activation makes the coolant easy to overcome the airflow fbllowing wheel rotation and to reach the grinding point. Furthermore, the fiushing effect ofthe vibration acceleration prevents the deposition and weld of chips.

The use of an ultrasonically activated coolant improves the roughness of a ground surface compared with that of an ordinary coolant. By evaluating the change in working surface conditions, it has been clarified that the ultrasonically activated coolant suppresses loading and wheel wear, and maintains a good the working surface condition. The flushing effect of the ultrasonically activated coolant, promoted by giant vibration acceleration, prevents the deposition and welding of chips on the working surface. Since the density of kinetic energy in the coolant stream increases, the activation helps the coolant to overcome the airflow due to wheel rotation and to reach the grinding point efficiently. This promotes the cooling and lubricating effects of coolant, and then protects the cutting edges from crushing, falling off and dulling. On the basis of the results, it can be said that the effects of coolant activation suppress the generation of scratches, and consequently improve the finished surface roughness.