Technological Experiments On Creep Feed Ultrasonic Grinding Ceramics(Al₂O₃)

Creep feed ultrasonic grinding technology will become a new way for the development of engineering ceramics machining technology. In order to further boost the development and application of it, comparative experiments of grinding Al₂O₃ ceramics with/without ultrasonic vibration were carried out on the refitted machine tool with the ultrasonic grinding device. In this paper, selecting certain grinding process parameters and grinding modes, comparative experiments were carried out with electroplate diamond wheels. Analytical investigation on the ground surface roughness, surface topography and grinding efficiency was carried out according to the experimental results.Firstly, the former ultrasonic grinding mechanism was refitted in respect of the system rigidity, accuracy and motion stability. And certain new equipments and clamps were used to insure the stability of the ultrasonic grinding process.Secondly, the ground surface quality of Al₂O₃ ceramics with creep feed ultrasonic grinding was analyzed, and the material removal mechanism was inferred. It's indicated that the polishing function was remarkable in the process of creep feed ultrasonic grinding when the direction of ultrasonic vibration was parallel to that of the grinding feed, the surface roughness processed by ultrasonic grinding was lower than that of conventional mechanical grinding. And it's also indicated in the experiment that in the process of creep feed Al₂O₃ ceramics with ultrasonic assistance the material was removed as brittle fracture, and grain pulverization and trans-granular fracture were the main material removal modes followed with intercrystalline fracture,elastic scratch and plastic flow.Meanwhile, the grinding characteristic of creep feed ultrasonic grinding Al₂O₃ ceramics was analyzed according to the experimental results and ground surface topographies, which provided theoretical and experimental references for the further study on the technology of creep feed ultrasonic grinding Al₂O₃ ceramics.