Study of the 3D Topography Modelling and Control Method for Blazed Gratings Induced by Ultrasonic Elliptical Vibration Cutting

To overcome the technical difficulties for accurately predicting and controlling the 3D topography of nanoscale blazed gratings induced by ultrasonic elliptical vibration cutting,an iterative surface updating method for grating 3D topography is proposed by considering the synthetic cutting trajectory,three-dimensional geometric characteristics of cutting tool as well as workpiece material properties.The effect of minimum uncut chip thickness and intensive interaction between tool flank and machined surface are also included.Taking the ideal grating 3D topography with 1μm spacing,12 ° blazed angle and 106 nm grating height as an example,the deterministic generation of blazed grating with desired 3D topography is realized by setting the process parameters based on the above method.The experimental results show that the machining errors of grating spacing,blazed angle and grating height are 1.1%,4.1% and 15.0% respectively,which indicates the feasibility and accuracy of the proposed control method for 3D topogra