Study on surface Morphology of 7075 aluminum alloy deep hole by two-dimensional ultrasonic elliptical vibration turning

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.