A Study On Error Analysis And Processing Of Laser Projective Ablation By Galvanometer Scanning On Freeform Surface

Under the background of global competition, cross-scale free-form surface parts widely used in the high-grade precise and advanced fields such as aerospace, energy, shipbuilding industry, to achieve the special surface performance, required to manufacture large-format of surface microstructures on the part surface of cemented carbide, ceramics, composite multilayer film and other hard processing material. The usual way is through the five-axis CNC machine tools for precision milling/grinding, but it is not only difficult to take account of both high precision and efficiency processing, but also impossible to process flexible materials.Laser ablation technology based on two galvanometer scanners has many advantages such as high focused laser energy, the small laser spot, non-contact processing, etc,and galvanometer with light quality, small moment of inertia, big acceleration especially suitable for microstructure of high efficiency, high precision ablation, can make up for the inadequacy of traditional mechanical processing, according to the principle of light parallel projection and by means of the special property of the depth of focus of focused laser beam in this paper. And with the help of the precise positioning of multi-axis CNC machine, the galvanometer can achieve large free-form surface ablation processing.Because the laser precision machining has so many advantages, this paper aims to study the following contents based on Laser Projective Ablation by Galvanometer Scanning(LPAGS).(1) According to the LPAGS, Analyzes in detail its multiple optimal discriminant rules of large complex free-form surface under the condition of the partition optimization algorithm, and established the three basic principles of partition optimization algorithm: rotational partition rule, planar subdivision rule and depth of focus depth rule.(2) According to the LPAGS, analysis the galvanometer distortion error, and the correction precision of different correction methods to make the assessment, and the layered splicing error and fragmentation splicing error are analyzed in detail.(3) According to the LPAGS, analyses the motion error of five-axis machine, and according to the principle of homogeneous transformation its space error model is established.(4)Through experiment to find out plane to the surface of laser spot size, the energy density changing with Angle change rule, and theoretical analysis, find out the reason of its change rule. And set up 335 nm uv laser and PI membrane at different laser incident Angle, the interaction between the etching depth, the mathematical model of size change with Angle.(5)Through orthogonal experiment to get the influence of processing parameters on the machining quality, machining efficiency. For cylinder respectively with a shard machining and partition way on the processing, research has shown that partition processing in both machining quality, machining efficiency is superior to the lamination processing.