Characteristics Of Ion Beam Polishing Removed

With the rapid development of modern science and technology, Electronics, Optics,and Astronomy have a growing demand for ultra-smooth surface, and require thesurface accuracy of the key parts to reach the sub-nanometer standard. With thisdemand leading to the development of precision machining techniques, ion beampolishing techniques have come into being. The technology is an advanced processingtechnology which is based on the sputtering theory, and is a kind of polishing processon the atomic level of the characters of no stress and non-contact. As the principle ofcomputer control optical surface forming process is known, the removal function is animportant factor to determine the precision of ion beam polishing. In order to improvethe machining accuracy，This paper mainly focus on the research of ion beam polishingremoval function and involved knowledge. In the process of ion beam polishingmachine, the appropriate removal function model estimation method needs to beselected, to develop a more precise mathematical model of the ion beam polishingremoval function. By theoretical simulation, All relevant factors affecting the removalfunction accuracy should be Analyzed, to correct the function and improve the accuracyof estimated removal function model. According to the removal function model and theprinciple of ion beam polishing, the dwell time of corresponding point will becalculated, and completing the processing by computer, the final surface accuracy willbe able to reach the desired requirements. In this thesis, starting from the ion beam offormatting removal function and using the Ar ion beam bombardment quartz glass asthe model for the study, the main research content of this paper includes the followingaspects:(1) Research of the ion beam characters. It includes the interaction collisionprocess between the ion beam and the solid surface, ion beam energy loss ofthe ion beam in solid, as well as the movement range research of the ion beamin solid, aimed at researching the ion beam polishing theory, environmentalimpact factors, and the surface damage of polished workpiece. (2) Establishment and analysis of the Sputtering model. It contains theestablishment of two-body collision model, the analysis of the Sigmundtheoretical model, corresponding analysis and simulation of the sputtering yieldand the factors affecting it. The purpose is to analyze the ion beam polishingaccuracy and efficiency, also lay the foundation for setting up the removalfunction model.(3) The establishment of the removal function mathematical model. The actualremoval function model is achieved by experiment. Respectively, by using themethod of least squares and the Gauss-Newton iterative method, the removalfunction is fitted and analyze on the accuracy of the two methods of fittingcomparative analysis. Building the removal function model accurately canimprove the calculation precision of dwell time, so as to achieve the purpose ofprecise machining.(4) Theory analysis of the important factors influencing removal function in actualprocessing. It includes analysis of the effects of incident angle on removalfunction, and analysis of effects of processing targets and distance distributionon removal function. The situation of three axis system processing largecurvature workpiece is also be analyzed precisely and corrected. Finally,specific process requirements are got in the processing to achieve the stabilityof removal function and improve the machining precision.