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Optical glass is an isotropic amorphous solid material, due to its excellent performance, it has been widely used in various fields. However, during the milling process, the optical glass will have defects such as chipping and cracks on the surface, import and export, and side edges, these defects seriously affect the application of optical glass. In order to study the formation mechanism of defects such as chipping and cracks during optical glass processing, experimental and theoretical study of optical glass milling using ultrasonic vibration-assisted milling (UVAM), the chipping depth model of the export edge collapse was established. The results show that, the main reason for the edge chipping defect is that the optical glass will crack on the subsurface during processing, the propagation of these cracks causes the matrix material to tear and crumble. By comparing and analyzing the results of ultrasonic vibration milling and ordinary milling, ultrasonic vibration can significantly reduce this phenomenon, and it is found that the cutting depth and feed per tooth have a great influence on the export chipping depth value, and the influence of spindle speed is less. In addition, when the amplitude of the ultrasonic wave is applied, not only the import and export edge chipping phenomenon can be significantly improved, but also the surface quality can be significantly improved. Therefore, the application of ultrasonic vibration-assisted milling to the processing of optical glass can improve the surface and edge quality, which is help improve the application range of optical glass.

In order to obtain 7075 aluminum alloy deep hole tube parts with better surface quality, the two-dimensional ultrasonic elliptical vibration turning (2D-UEVT) was studied. The tool tip trajectory model and the surface roughness model of 2D-UEVT deep hole were established. It was found that 2D-UEVT could obtain lower surface roughness than common turning (CT) through analyzing the theoretical model. Finally, the effects of turning parameters and acoustic parameters on surface morphology were studied by four-factor four-level orthogonal test. The experimental results indicated that the surface roughness Ra value decreased in different degrees after the 2D-UEVT. However, various turning parameters and acoustic parameters had different effects on the reduction of Ra. With the increase of the feed rate and spindle speed, the surface roughness Ra shows a trend of decreasing first and then increasing. With the increase of ultrasonic amplitude, the Ra displayed increasing first and then decreasing. The influence of cutting depth on the roughness is not significant. The results demonstrated that better surface texture and surface quality can be obtained with lower feed rate, medium ultrasonic amplitude and spindle speed.

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