Parameter Adaptive Model Of Ultra-short Pulse Laser And Its Application In Post Processing

In the NC machining of ultra-short pulse laser,the mismatch between parameters of the laser and the processing speed will lead to too large or too small processing width and depth.Adaptive control of laser parameters is an important way to solve this problem.The existing methods of laser parameter adaptive control are basically aimed at long pulse laser processing,and cannot be directly used in ultra-short pulse laser processing.Therefore,based on the mechanism of ultra-short pulse laser processing and some actual processing data,a method of ultra-short pulse laser parameter adaptive control and its application in post processing are studied in this paper.Firstly,on the basis of the calculation method of the material ablative threshold under the situation of ultra-short pulse laser drilling,a calculation method of the material ablative threshold under the situation of ultra-short pulse laser dynamically machining is put forward.And a method of calculating parameters of ultra-short pulse laser is presented after analyzing the intrinsic rule between the processing size and processing parameters by related theory of the threshold effect and actual processing data.Secondly,in view of the too large processing size,an adaptive division method to divide a large processing dimension into some smaller processing dimensions is put forward,and methods of calculating the division time and the single processing size are given.Considering limitations of the hardware performance and the constraint of ablation threshold,some constraint detection rules are defined and applied to the applicability detection of laser parameters.On the basis of the above research,a model of the ultra-short pulse laser parameter adaptive control is built.Thirdly,on the basis of the post processing flow of the ultra-short pulse laser NC machining,an application method of the ultra-short pulse laser parameter adaptive control model is designed,in which the special DXF file structure design,the machine tool shaft motion coordinate calculation and the NC program generation are involved.Finally,the calculated parameters of the ultra-short pulse laser parameter adaptive control model are compared with the laser parameters used in actual processing to verify the correctness of the ultra-short pulse laser parameter adaptive control model.A prototype of post processing system with parameter adaptive control characteristic is built and the application feasibility of the ultra-short pulse laser parameter adaptive control model is verified by a post processing of a DXF file.