| With the rapid development of science and technology, modern industry isconstantly improving the requirements of the machinery, which includes thematerials, precision and shape of various precision parts. As a result, the microfabrication is paid more and more attention. The method of special machineryhas a unique advantage in mechanical micro fabrication, ultrasonic vibrationassisted machining of the special machinery has an excellent effect in the brittlematerials, which include ceramics, glass and composite metal. A UAMD(Ultrasonic Assisted Micro-Drilling) is a key micro and non-traditionalmachining technology based on conventional high speed micro-drillingcombined with vibration cutting. By using ultrasonic assisted micro-drilling canproduct the micro hole efficiency and high quality, and the diameter of microhole is below0.2mm and depth to diameter is about10. These micro holeswidely exist in engine nozzle, blade of gas turbine, microstructured hydrophobicsurfaces and all kinds of micromachine. Compared with conventional high speedmicro drilling, when using the UAMD the chip discharge condition is improved.The condition that chip blocking the microhole causes the micro drill fracture and breakage is reduction and micro drill is more easily to drill into theworkpiece and centering. At the same time, the thrust force and torque in theUAMD is smaller than that of conventional high speed drilling.In this paper, the UAMD has been re-designed and re-researched based onthe trends and problems of the processing methods about the UAMD. Currently,ultrasonic assisted cutting of the microfabrication has not special vibratingmechanism or machine tools, and the exciting ultrasonic vibration cuttingdevices work mainly by applying ultrasonic vibration in the one end of the toolhead, which restrict the promotion and application of the ultrasonic vibrationassisted machining. So, in this paper, expecting to develop a shaker which canbe used on the UAMD，which can apply the ultrasonic vibration to one end ofthe workpiece. Thus, the precision of drilling microporous can not only beimproved, but the versatility of the micromachined ultrasonic vibration assistedvibration device can be increased. As a result, processing costs have beenreduced and the ultrasonic vibration assisted machining can be better applied.In this paper, first of all, the basic theory of ultrasonic vibration assistedmachining is summarized, development of ultrasonic vibration assistedmachining and basic components are introduced and characteristics of varioustypes of ultrasonic vibration device are summarized.Secondly, the main component of the ultrasonic vibration table is calculatedand designed, which includes ultrasonic transducers, ultrasonic amplitudetransformer, vibration platform, fixtures and so on. Besides, modal analysis has been done by ANSYS software and the optimal design is done about the majorcomponents.Furthermore, ultrasonic vibration table which is under the premise to meetthe project needs is simplified and experiments have been done about theUAMD, and the results are analyzed. The micropore wall gained by high-speedmicro drilling and ultrasonic vibration drilling are observed by using scanningelectron microscope, the results show that the micropore wall gained byultrasonic vibration drilling is more smoother and good roundness pore entrance,a small glitch, better processing effect. At the same time, the results show thatthe designed ultrasonic vibration assisted units is reasonable and effective meanswhich can meet the engineering requirements.Finally, summarizes have been done on ultrasonic vibration table, at thesame time, exciting shortages are listed about the table and new demands areadvanced about the application of the entire equipment. At last, the outlook offollow-up work have been given. |
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