An investigation of the mechanism and benefits of ultrasonic vibration-assisted drilling of hard brittle materials such as Hotan jade

摘要

The ultrasonic vibration-assisted drilling process and the surface micro characteristics of Hotan jade were evaluated in detail. Because of the special physical properties of Hotan jade, traditional machining methods have great limitations. In consequence, it is difficult to achieve the required precision and surface quality. In this study, the physical properties of Hotan jade were considered and its unique cutting and machinability characteristics were evaluated for comparison purposes. The design principles of UV drilling and the important components of such a system were examined. The material removal mechanism of UV drilling was evaluated in detail. Finally, comparative tests using UV drilling and traditional drilling were carried on Hotan jade. The test results were evident from the degree of tool wear, degree of reaming, the extent of damage at the entrance to the drilled hole, the outlet burr and the roughness of the hole surface. The results of the machining trials confirmed that UV drilling not only was an easier process, but the straightness of the hole could be guaranteed, and the machined quality and drilling efficiency usually were better than was the case using traditional machining.