Papers by Keyword: Ultrasonic Vibration Lapping

Abstract: In this paper, the natural frequency and the vibration mode of the lapping tool in ultrasonic vibration lapping are analyzed, the resonance mechanism of the lapping tool is researched by establishing its mechanical model and displacement equation, and the experimental study is carried out in ultrasonic vibration lapping of engineer ceramics. The conclusions include: 1) The natural frequency of the designed lapping tool is ; 2) The acoustic system in ultrasonic vibration lapping is simplified to equivalent many-degrees of freedom system, while the damp is ignored, the lapping tool is resonant with itself-natural frequency, the joint of the horn and the lapping tool is a displacement node, and the whole system is in resonant condition. 3）While the experimental condition is no-load and ultrasonic, the vibration frequency of the lapping tool is 21.3125 , which is further closed to the calculated natural frequency, at that time the amplitude of the lapping tool is maximal and the system is in resonant condition. Moreover, while the resonance frequency of the horn and the lapping tool is different, the good vibration effect of the lapping tool can be obtained by adjusting the excitation frequency of generator.

Abstract: Based on the machining principle of ultrasonic vibration lapping, the surface roughness characteristics of plastic difficult-to-machine titanium alloys are studied through experiments using self-developed ultrasonic vibration lapping device. And the effects of workpiece speed, ultrasonic amplitude and grain size on surface roughness were researched by using single-factor testing way. The research results show that surface roughness is decreased to a certain extent for the assistance of ultrasonic vibration. The corresponding results provide certain reference value for the optimization of processing parameter in ultrasonic vibration lapping.

Abstract: Hard-brittle materials have been popular used in manufacture experience because of their excellent performances. However the low plasticity, frangibility and non-conduction make the machining very difficult, especially in ultra-precise surface fabrication. Therefore, ultrasonic vibration is introduced to conventional lapping for the purpose of proper lapping force, higher removal rate and fine surface quality. Through conventional and ultrasonic lapping experiment of hard-brittle materials with different lapping parameters and different vibration models, the empirical formula of lapping force in ultrasonic lapping is deduced by orthogonal regression analysis, the optimum lapping parameters are put forward and the primary and secondary influencing sequence of parameters on lapping force is presented. Moreover, the influencing rule of different lapping parameters such as rotational speed, feed speed, oilstone grit and lapping depth etc. on lapping force is carried out. Experimental results show that ultrasonic vibration lapping is a high efficient processing method adapting to hard-brittle materials.