Possibility of metal processing using ultrasonic cavitation jet

Utilizing a high-intensity ultrasonic cavitation, a processing experiment w as conducted with the aim of performing volumetric flow adjustment of a fue l jet nozzle to be used for a small engine, which cannot be carried out by a method such as machining. At the bottom of the nozzle used for the experi ment, which is in the shape of a cup, a nozzle hole with a diameter of 0.15 mm. is drilled. In this experiment. we make adjustments in the volumetric flow by grinding and removing the machining burr with the aid of the proces sing power of ultrasonic cavitation. The processing effect is highly depend ent on the ultrasonic cavitation intensity, In the experiment, the processi ng reservoir was filled with pressurized highly deaerated water to increase the processing force by allowing cavitation with high intensity to be gene rated. The processing principle is to utilize the effect of a cavitation je t flow passing through the nozzle hole. To restrain the intake of the bubbl es into the flow circuits during the pressure reduction cycle of the vibrat or, the water flow was discharged into a pressure reduction reservoir. By a llowing the horn tip with a diameter of 6 mm at a frequency of 28 kHz to ap proach the sample, followed by high-intensity ultrasonic irradiation, power ful cavitation was generated. As a result of the evaluation of the processi ng efficiency made based on the volumetric flow increase and microscopic ob servation of the nozzle. burrs smaller than 10 mum were almost entirely rem oved within 15 min of initial irradiation, resulting in a volumetric flow i ncrease of more than 0.4%/min. However, in the case of burrs of more than 1 0 mum, no force that could remove the burrs was found. It was surprising fo r the burrs to generate deformation rather than to be removed.